Displaying apparatus having light emitting device, method of manufacturing the same and method of transferring light emitting device

ABSTRACT

A displaying apparatus including: a panel substrate; a plurality of light emitting devices arranged on the panel substrate; and at least one connection tip disposed on one surface of each of the light emitting devices. Each of the light emitting devices includes a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers; and first and second electrode pads disposed on the light emitting structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.16/207,692, filed on Dec. 3, 2018, now issued as U.S. Pat. No.10,797,027, and claims priority from and the benefit of U.S. ProvisionalApplication No. 62/595,010, filed on Dec. 5, 2017, U.S. ProvisionalApplication No. 62/610,489, filed on Dec. 26, 2017, and U.S. ProvisionalApplication No. 62/694,353, filed on Jul. 5, 2018, which are herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND Field

Exemplary embodiments of the invention relate generally to a displayingapparatus having light emitting devices, a method of manufacturing thesame, and a method of transferring light emitting devices.

Discussion of the Background

Light emitting devices are semiconductor devices using light emittingdiodes which are inorganic light sources, and are used in various fieldssuch as displaying apparatuses, automobile lamps, general lighting, andthe like. Light emitting diodes have advantages such as long lifespan,low power consumption, and rapid response, and thus are rapidlyreplacing existing light sources.

In the meantime, a conventional light emitting diode has been mainlyused as a light source of a backlight unit in a displaying apparatus.Recently, a micro LED used in a displaying apparatus implementing adirect image using a light emitting diode has been developed.

A displaying apparatus generally implements various colors by usingmixed colors of blue, green and red. The displaying apparatus comprisesa plurality of pixels to implement various images, and each pixel hasblue, green, and red subpixels. A color of a particular pixel isdetermined through colors of these subpixels, and an image isimplemented by a combination of these pixels.

In the case of a micro LED display, micro LEDs are arranged on atwo-dimensional plane corresponding to each sub-pixel, and thus it isnecessary that a large number of micro LEDs are arranged on onesubstrate. However, the micro LED whose size is less than 200 microns,further less than 100 microns is very small, and various problems occurbecause of these small sizes. In particular, it is difficult to handlelight emitting diodes of a small size and it is not easy to mount alight emitting diode on a display panel.

The above information disclosed in this Background section is only forunderstanding of the background of the inventive concepts, and,therefore, it may contain information that does not constitute priorart.

SUMMARY

Exemplary embodiments of the inventive concepts provide a method ofmanufacturing a displaying apparatus by which a plurality of lightemitting devices formed on a growth substrate can be easily mounted on adisplay panel substrate and a displaying apparatus manufactured throughthe method.

Exemplary embodiments of the inventive concepts also provide a method oftransferring light emitting devices capable of safely transferring alarge amount of light emitting devices to a display panel substrate.

Additional features of the inventive concepts will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the inventive concepts.

A displaying apparatus according to an exemplary embodiment maycomprise: a panel substrate; a plurality of light emitting devicesarranged on the panel substrate; and at least one connection tipdisposed on one surface of each of the light emitting devices, whereineach of the light emitting devices may comprise a light emittingstructure comprising a first conductivity type semiconductor layer, asecond conductivity type semiconductor layer and an active layerinterposed between the first and second conductivity type semiconductorlayers; and first and second electrode pads disposed on the lightemitting structure.

A method of transferring light emitting device according to an exemplaryembodiment may comprise: forming a plurality of light emitting devicesregularly arranged on a substrate; forming a mask layer covering theplurality of light emitting devices, and having at least one hole overeach of the light emitting devices; forming a connection layer on themask layer, the connection layer being connected to the light emittingdevices through the holes; coupling a first temporary substrate to anupper surface of the connection layer; removing the substrate and themask layer from the light emitting devices; coupling a second temporarysubstrate to lower surfaces of the light emitting devices; andseparating the light emitting devices from the connection layer.

A method of transferring light emitting devices according to anexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a first mask layercovering the plurality of light emitting devices; coupling a firsttemporary substrate to an upper surface of the first mask layer;removing the substrate from the light emitting devices; forming a secondmask layer under the first mask layer, and having at least one holeunder each of the light emitting devices; forming a connection layerunder the second mask layer, the connection layer being connected to thelight emitting devices through the holes; coupling a second temporarysubstrate to a lower surface of the connection layer; removing the firsttemporary substrate and the first and second mask layers from the lightemitting devices; and separating the light emitting devices from theconnection layer.

A method of manufacturing a displaying apparatus according to anexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a mask layer coveringthe plurality of light emitting devices, and having at least one holeover each of the light emitting devices; forming a connection layer onthe mask layer, the connection layer being connected to the lightemitting devices through the holes; coupling a first temporary substrateto an upper surface of the connection layer; removing the substrate andthe mask layer from the light emitting devices; coupling a secondtemporary substrate to lower surfaces of the light emitting devices;separating the light emitting devices from the connection layer; andseparating at least one light emitting device among the plurality oflight emitting devices disposed on the second temporary substrate fromthe second temporary substrate.

A method of manufacturing a displaying apparatus according to anexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a first mask layercovering the plurality of light emitting devices; coupling a firsttemporary substrate onto the first mask layer; removing the substratefrom the light emitting devices; forming a second mask layer under thefirst mask layer, and having at least one hole under each of the lightemitting devices; forming a connection layer on the second mask layer,the connection layer being connected to the light emitting devicesthrough the holes; coupling a second temporary substrate to a lowersurface of the connection layer; removing the first temporary substrateand the first and second mask layers from the light emitting devices;and separating at least one light emitting device among the lightemitting devices on the second temporary substrate from the connectionlayer.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate exemplary embodiments of theinvention, and together with the description serve to explain theinventive concepts.

FIG. 1A is a plan view showing a light emitting apparatus according toan exemplary embodiment;

FIG. 1B is a cross-sectional view taken along the line I-I′ of FIG. 1A;

FIG. 2 is a cross-sectional view showing a light emitting deviceaccording to an exemplary embodiment;

FIG. 3 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment, which is taken along the line I-I′of FIG. 1A;

FIG. 4 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment;

FIG. 5 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment;

FIG. 6 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment;

FIG. 7 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment;

FIGS. 8A and 8B are cross-sectional views showing a light emittingapparatus according to an exemplary embodiment;

FIG. 9A is a plan view showing a light emitting device including lightemitting devices connected to each other in parallel according to anexemplary embodiment;

FIG. 9B is a cross-sectional view taken along a line II-IF of FIG. 9A;

FIG. 10 is a plan view showing a light emitting apparatus includinglight emitting devices connected to each other in series according to anexemplary embodiment;

FIG. 11 is a flowchart showing a transferring method after manufacturinga light emitting device in a manufacturing method of a light emittingapparatus according to an exemplary embodiment;

FIGS. 12A, 12B, 12C, 12D, 12E, 12F, 12G, 12H, 12I, 12J, 12K, 12L, 12M,and 12N are cross-sectional views showing in detail a manufacturingmethod of a light emitting device and a transferring method of the lightemitting device in order;

FIGS. 13A, 13B, 13C, 13D, and 13E are cross-sectional views showing amanufacturing method of a light emitting device and a transferringmethod of the light emitting device according to another exemplaryembodiment;

FIGS. 14A, 14B, 14C, 14D, 14E, 14F, 14G, 14H, 14I, 14J, 14K, 14L, and14M are cross-sectional views showing a manufacturing method of a lightemitting apparatus according to an exemplary embodiment

FIGS. 15A, 15B, 15C, 15D and 15E are conceptual views sequentiallyshowing a method of simultaneously transferring plural light emittingdevices;

FIG. 16 is a view showing processes of forming a plurality of pixelunits in a substrate of sufficient size and cutting the substrate intodisplay units of various sizes;

FIG. 17 is a view showing a process of assembling and mounting displayunits of various sizes on a base substrate such as a printed circuitboard;

FIG. 18 is a plan view showing a displaying apparatus manufactured bythe above described manufacturing method;

FIG. 19 is an enlarged plan view showing a portion P3 of FIG. 18;

FIG. 20 is a block diagram showing a displaying apparatus according toan exemplary embodiment;

FIG. 21A is a circuit diagram showing one pixel among pixels for apassive matrix type displaying apparatus;

FIG. 21B is a circuit diagram showing a first pixel among pixels for anactive matrix type displaying apparatus;

FIG. 22 is a perspective view showing a large-sized multi-moduledisplaying apparatus e according to an exemplary embodiment;

FIG. 23 is a schematic plan view illustrating a displaying apparatusaccording to another exemplary embodiment;

FIGS. 24A and 24B are a schematic plan view and a cross-sectional viewillustrating a light emitting device of the displaying apparatusaccording to the other exemplary embodiment, respectively;

FIG. 24C is a schematic cross-sectional view illustrating a modifiedexample of the light emitting device;

FIGS. 25A, 25B, 25C, 25D, 25E, 25F, 25G, 25H, 25I, 25J, and 25K areschematic cross-sectional views illustrating a method of manufacturingthe displaying apparatus according to the other exemplary embodiment;

FIGS. 26A, 26B, 26C, 26D, 26E, 26F, 26G, 26H, 26I, 26J, 26K, and 26L areschematic cross-sectional views illustrating a method of manufacturing adisplaying apparatus according to another exemplary embodiment;

FIGS. 27A, 27B, 27C, 27D, 27E, 27F, 27G, 27H, 27I, 27J, and 27K areschematic cross-sectional views illustrating a method of manufacturing adisplaying apparatus according to another exemplary embodiment;

FIGS. 28A, 28B, 28C, 28D, 28E, 28F, 28G, 28H, 28I, 28J, 28K, 28L, 28M,28N, and 28O are plan views illustrating modified examples of the lightemitting device;

FIG. 29A is a schematic plan view illustrating a light emitting deviceaccording to another exemplary embodiment of another exemplaryembodiment;

FIG. 29B is a schematic cross-sectional view taken along the line ofC-C′;

FIG. 30A is a schematic plan view illustrating a pixel region accordingto another exemplary embodiment; and

FIG. 30B is schematic cross-sectional view taken along the line of D-D′.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of various exemplary embodiments or implementations of theinvention. As used herein “embodiments” and “implementations” areinterchangeable words that are non-limiting examples of devices ormethods employing one or more of the inventive concepts disclosedherein. It is apparent, however, that various exemplary embodiments maybe practiced without these specific details or with one or moreequivalent arrangements. In other instances, well-known structures anddevices are shown in block diagram form in order to avoid unnecessarilyobscuring various exemplary embodiments. Further, various exemplaryembodiments may be different, but do not have to be exclusive. Forexample, specific shapes, configurations, and characteristics of anexemplary embodiment may be used or implemented in another exemplaryembodiment without departing from the inventive concepts.

Unless otherwise specified, the illustrated exemplary embodiments are tobe understood as providing exemplary features of varying detail of someways in which the inventive concepts may be implemented in practice.Therefore, unless otherwise specified, the features, components,modules, layers, films, panels, regions, and/or aspects, etc.(hereinafter individually or collectively referred to as “elements”), ofthe various embodiments may be otherwise combined, separated,interchanged, and/or rearranged without departing from the inventiveconcepts.

The use of cross-hatching and/or shading in the accompanying drawings isgenerally provided to clarify boundaries between adjacent elements. Assuch, neither the presence nor the absence of cross-hatching or shadingconveys or indicates any preference or requirement for particularmaterials, material properties, dimensions, proportions, commonalitiesbetween illustrated elements, and/or any other characteristic,attribute, property, etc., of the elements, unless specified. Further,in the accompanying drawings, the size and relative sizes of elementsmay be exaggerated for clarity and/or descriptive purposes. When anexemplary embodiment may be implemented differently, a specific processorder may be performed differently from the described order. Forexample, two consecutively described processes may be performedsubstantially at the same time or performed in an order opposite to thedescribed order. Also, like reference numerals denote like elements.

When an element, such as a layer, is referred to as being “on,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, connected to, or coupled to the other element or layer orintervening elements or layers may be present. When, however, an elementor layer is referred to as being “directly on,” “directly connected to,”or “directly coupled to” another element or layer, there are nointervening elements or layers present. To this end, the term“connected” may refer to physical, electrical, and/or fluid connection,with or without intervening elements. Further, the D1-axis, the D2-axis,and the D3-axis are not limited to three axes of a rectangularcoordinate system, such as the x, y, and z—axes, and may be interpretedin a broader sense. For example, the D1-axis, the D2-axis, and theD3-axis may be perpendicular to one another, or may represent differentdirections that are not perpendicular to one another. For the purposesof this disclosure, “at least one of X, Y, and Z” and “at least oneselected from the group consisting of X, Y, and Z” may be construed as Xonly, Y only, Z only, or any combination of two or more of X, Y, and Z,such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items.

Although the terms “first,” “second,” etc. may be used herein todescribe various types of elements, these elements should not be limitedby these terms. These terms are used to distinguish one element fromanother element. Thus, a first element discussed below could be termed asecond element without departing from the teachings of the disclosure.

Spatially relative terms, such as “beneath,” “below,” “under,” “lower,”“above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), andthe like, may be used herein for descriptive purposes, and, thereby, todescribe one elements relationship to another element(s) as illustratedin the drawings. Spatially relative terms are intended to encompassdifferent orientations of an apparatus in use, operation, and/ormanufacture in addition to the orientation depicted in the drawings. Forexample, if the apparatus in the drawings is turned over, elementsdescribed as “below” or “beneath” other elements or features would thenbe oriented “above” the other elements or features. Thus, the exemplaryterm “below” can encompass both an orientation of above and below.Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90degrees or at other orientations), and, as such, the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” “comprising,” “includes,” and/or “including,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orgroups thereof, but do not preclude the presence or addition of one ormore other features, integers, steps, operations, elements, components,and/or groups thereof. It is also noted that, as used herein, the terms“substantially,” “about,” and other similar terms, are used as terms ofapproximation and not as terms of degree, and, as such, are utilized toaccount for inherent deviations in measured, calculated, and/or providedvalues that would be recognized by one of ordinary skill in the art.

Various exemplary embodiments are described herein with reference tosectional and/or exploded illustrations that are schematic illustrationsof idealized exemplary embodiments and/or intermediate structures. Assuch, variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, exemplary embodiments disclosed herein should notnecessarily be construed as limited to the particular illustrated shapesof regions, but are to include deviations in shapes that result from,for instance, manufacturing. In this manner, regions illustrated in thedrawings may be schematic in nature and the shapes of these regions maynot reflect actual shapes of regions of a device and, as such, are notnecessarily intended to be limiting.

As customary in the field, some exemplary embodiments are described andillustrated in the accompanying drawings in terms of functional blocks,units, and/or modules. Those skilled in the art will appreciate thatthese blocks, units, and/or modules are physically implemented byelectronic (or optical) circuits, such as logic circuits, discretecomponents, microprocessors, hard-wired circuits, memory elements,wiring connections, and the like, which may be formed usingsemiconductor-based fabrication techniques or other manufacturingtechnologies. In the case of the blocks, units, and/or modules beingimplemented by microprocessors or other similar hardware, they may beprogrammed and controlled using software (e.g., microcode) to performvarious functions discussed herein and may optionally be driven byfirmware and/or software. It is also contemplated that each block, unit,and/or module may be implemented by dedicated hardware, or as acombination of dedicated hardware to perform some functions and aprocessor (e.g., one or more programmed microprocessors and associatedcircuitry) to perform other functions. Also, each block, unit, and/ormodule of some exemplary embodiments may be physically separated intotwo or more interacting and discrete blocks, units, and/or moduleswithout departing from the scope of the inventive concepts. Further, theblocks, units, and/or modules of some exemplary embodiments may bephysically combined into more complex blocks, units, and/or moduleswithout departing from the scope of the inventive concepts.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure is a part. Terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and should not be interpreted in anidealized or overly formal sense, unless expressly so defined herein.

A displaying apparatus according to an exemplary embodiment maycomprise: a panel substrate; a plurality of light emitting devicesarranged on the panel substrate; and at least one connection tipdisposed on one surface of each of the light emitting devices, whereineach of the light emitting devices may comprise a light emittingstructure comprising a first conductivity type semiconductor layer, asecond conductivity type semiconductor layer and an active layerinterposed between the first and second conductivity type semiconductorlayers; and first and second electrode pads disposed on the lightemitting structure.

In one exemplary embodiment, the at least one connection tip is disposedon the light emitting structure, and may be disposed between the firstand second electrode pads.

A thickness of the at least one connection tip may be smaller thanthicknesses of the first and second electrode pads. Accordingly, anupper end of the connection tip is located lower than upper ends of thefirst and second electrode pads.

In one exemplary embodiment, the at least one connection tip may bedisposed on an opposite side of the light emitting structure opposite tothe first and second electrode pads.

The at least one connection tip may contact the first conductivity typesemiconductor layer.

In addition, a plurality of connection tips may be disposed on each ofthe light emitting devices, and wherein the plurality of connection tipsarranged on each of the light emitting devices may be disposedasymmetrically to at least one alignment direction of the light emittingdevices arranged on the panel substrate.

Here, the at least one connection tip may comprise three connection tipsarranged in triangular shape, wherein one of the three connection tipsmay be disposed along a first row, and the others may be disposed alonganother row adjacent to the first row.

The at least one connection tip may further comprise a connection tipdisposed at a center of the light emitting device, wherein theconnection tip disposed at the center of the light emitting device maybe disposed in the triangle formed by the three connection tips.

Furthermore, the connection tips may have right triangular shapes. Inaddition, the connection tip disposed at the center of the lightemitting device may be disposed in a different direction from that ofthe other connection tips.

The plurality of connection tips may have different thicknesses.

In the meantime, an area ratio of the connection tip to a planar area ofthe light emitting device may be 1.2% or less.

The first electrode pad may be electrically connected to the firstconductivity type semiconductor layer through a via-hole formed in thesecond conductivity type semiconductor layer and the active layer.

In addition, the light emitting device may further comprise aninsulation layer covering the second conductivity type semiconductorlayer and side surfaces of the first conductivity type semiconductorlayer.

The light emitting device may further comprise an ohmic-layer disposedon the second conductivity type semiconductor layer, and the insulationlayer may cover the ohmic-layer and side surfaces of the firstconductivity type semiconductor layer.

The displaying apparatus may further comprise: bumps electricallyconnected to the light emitting devices; a base substrate disposingopposite to the bumps and transmitting light emitted from the lightemitting devices; a step adjustment layer disposed between the bumps andthe light emitting devices to cover the light emitting devices; and anadhesive layer disposed between the base substrate and the lightemitting devices to adhere the light emitting devices to the basesubstrate, wherein the step adjustment layer and the adhesive layercover side surfaces of the light emitting device.

In addition, the displaying apparatus may further comprise a protectionlayer covering side surfaces of the bumps and the step adjustment layer.

Furthermore, the connection tip may be buried in the adhesive layer.

The base substrate may have irregularities on the surface thereof.

The displaying apparatus may further comprise: a light blocking layerdisposed between the adhesive layer and the base substrate, wherein thelight blocking layer may have a window transmitting light generated inthe light emitting device, and a width of the window may be smaller thanthat of the light emitting device.

A method of transferring light emitting device according to anotherexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a mask layer coveringthe plurality of light emitting devices, and having at least one holeover each of the light emitting devices; forming a connection layer onthe mask layer, the connection layer being connected to the lightemitting devices through the holes; coupling a first temporary substrateto an upper surface of the connection layer; removing the substrate andthe mask layer from the light emitting devices; coupling a secondtemporary substrate to lower surfaces of the light emitting devices; andseparating the light emitting devices from the connection layer.

Furthermore, the method of transferring light emitting device mayfurther comprise transferring at least one light emitting device amongthe plurality of light emitting devices disposed on the second temporarysubstrate to another substrate.

Here, separating the light emitting devices from the connection layermay be performed by applying an external force to one side of the secondtemporary substrate in a direction opposite to the first temporarysubstrate.

As the connection layer and the light emitting devices are separated bythe external force, connection tips as portions of the connection layermay remain on the light emitting devices.

In addition, in the step of coupling the first temporary substrate, thefirst temporary substrate may be coupled to the upper surface of theconnection layer so as to dispose a film portion between the connectionlayer and the first temporary substrate.

The method may further comprise, after the mask layer is removed,removing the first temporary substrate disposed over the light emittingdevices from the film portion, wherein the second temporary substratemay be coupled to lower surfaces of the light emitting devices after thefirst temporary substrate is removed.

A method of transferring light emitting device according to anotherexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a first mask layercovering the plurality of light emitting devices; coupling a firsttemporary substrate to an upper surface of the first mask layer;removing the substrate from the light emitting devices; forming a secondmask layer under the first mask layer, and having at least one holeunder each of the light emitting devices; forming a connection layerunder the second mask layer, the connection layer being connected to thelight emitting devices through the holes; coupling a second temporarysubstrate to a lower surface of the connection layer; removing the firsttemporary substrate and the first and second mask layers from the lightemitting devices; and separating the light emitting devices from theconnection layer.

When the light emitting devices are separated from the connection layer,a portion of the connection layer may remain on at least one of thelight emitting devices to form a connection tip.

A method of manufacturing a displaying apparatus according to anotherexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a mask layer coveringthe plurality of light emitting devices, and having at least one holeover each of the light emitting devices; forming a connection layer onthe mask layer, the connection layer being connected to the lightemitting devices through the holes; coupling a first temporary substrateto an upper surface of the connection layer; removing the substrate andthe mask layer from the light emitting devices; coupling a secondtemporary substrate to lower surfaces of the light emitting devices;separating the light emitting devices from the connection layer; andseparating at least one light emitting device among the plurality oflight emitting devices disposed on the second temporary substrate fromthe second temporary substrate.

Separating the light emitting devices from the connection layer may beperformed by applying an external force to one side of the secondtemporary substrate in a direction perpendicular to the first temporarysubstrate.

A method of manufacturing a displaying apparatus according to anotherexemplary embodiment may comprise: forming a plurality of light emittingdevices regularly arranged on a substrate; forming a first mask layercovering the plurality of light emitting devices; coupling a firsttemporary substrate onto the first mask layer; removing the substratefrom the light emitting devices; forming a second mask layer under thefirst mask layer, and having at least one hole under each of the lightemitting devices; forming a connection layer on the second mask layer,the connection layer being connected to the light emitting devicesthrough the holes; coupling a second temporary substrate to a lowersurface of the connection layer; removing the first temporary substrateand the first and second mask layers from the light emitting devices;and separating at least one light emitting device among the lightemitting devices on the second temporary substrate from the connectionlayer.

Here, when the light emitting device is separated from the connectionlayer, a portion of the connection layer may remain on the lightemitting device to form a connection tip.

The present disclosure may be variously modified and realized in manydifferent forms, and thus specific embodiments will be exemplified inthe drawings and described in detail hereinafter. However, the presentdisclosure should not be limited to the specific disclosed forms, and beconstrued to include all modifications, equivalents, or replacementsincluded in the inventive concepts.

The present disclosure relates a light emitting device including apixel. The light emitting device in the present disclosure includes adisplaying apparatus and/or a lighting device including a light emittingdevice. In the light emitting device, in a case where light emittingdevices are used as pixels that display an image, the light emittingdevice may be used as the displaying apparatus. The displaying apparatusincludes a television set, a tablet computer, an e-book displayingapparatus, a computer monitor, a kiosk, a digital camera, a gameconsole, a mobile phone, a personal digital assistant (PDA), alarge-sized outdoor/indoor display board, or the like. The lightingdevice may include a backlight used for the displaying apparatus, anindoor/outdoor lighting device, a street light device, or a vehiclelighting device.

The light emitting device according to an exemplary embodiment includesmicro-light emitting devices. The micro-light emitting devices may beelements with a width or length of about 1 micrometer to about 800micrometers scale, about 1 micrometer to about 500 micrometers scale, orabout 10 micrometers to about 300 micrometers scale. However, themicro-light emitting devices do not need to have the width or length inthe above-mentioned ranges and, if necessary, may have a smaller orlarger width or length.

Hereinafter, exemplary embodiments will be explained in detail withreference to the accompanying drawings.

FIG. 1A is a plan view showing a light emitting device according to anexemplary embodiment, and FIG. 1B is a cross-sectional view taken alongthe line I-I′ of FIG. 1A.

Referring to FIGS. 1A and 1B, the light emitting apparatus according tothe exemplary embodiment includes a substrate 10 and a pixel unit 110disposed above the substrate 10 and including at least one pixel 111.

The substrate 10 includes at least one pixel area 10 d and a non-pixelarea 10 nd surrounding the pixel area 10 d. The pixel area 10 dcorresponds to an area in which the pixel 111 is disposed and throughwhich a light exiting from a light emitting device 150 described latertravels to be perceived by a user. The non-pixel area 10 nd correspondsto an area except for the pixel area 10 d. The non-pixel area 10 nd isprovided adjacent to at least one side portion of the pixel 111, and inthe exemplary embodiment, the non-pixel area 10 nd is provided tosurround the pixel area 10 d.

The substrate 10 may be formed of a light transmitting insulatingmaterial. The expression of “the substrate 10 has the light transmittingproperty” indicates various cases where the substrate 10 is transparentto transmit the light entirely, the substrate 10 is semi-transparent totransmit only light having a specific wavelength, and the substrate 10is partially transparent to transmit only a portion of the light havingthe specific wavelength.

As the material for the substrate 10, a glass, a quartz, an organicpolymer, or an organic-inorganic composite material may be used, howeverit should not be limited thereto or thereby. That is, the material forthe substrate 10 should not be particularly limited as long as thematerial is optically transparent and insulative.

Each pixel unit 110 is a minimum unit that displays the image and thepixel unit is provided in plural in the display. Each pixel unit 110 mayemit a white light and/or a color light. Each pixel unit 110 may includeone pixel 111 emitting one color or may include plural pixels 111different from each other to emit the white light and/or the color lightobtained by combining different colors. For example, each pixel unit 110may include first, second, and third pixels 111 a, 111 b, and 111 c.

The pixel 111 is provided in the pixel area 10 d of the substrate 10.The pixel 111 is provided in one pixel area 10 d in a group orone-to-one fashion according to embodiments. In other words, each pixelunit 110 may be provided with at least one pixel 111, for example, eachpixel unit 110 may include the first, second, and third pixels 111 a,111 b, and 111 c. The first, second, and third pixels 111 a, 111 b, and111 c are provided in first, second, and third pixel areas 10 a, 10 b,and 10 c, respectively. The first, second, and third pixels 111 a, 111b, and 111 c may be implemented by first, second, and third lightemitting devices 150 a, 150 b, and 150 c that emit lights havingdifferent wavelength bands from each other. That is, when the lightsemitted by the first, second, and third light emitting devices 150 a,150 b, and 150 c are referred to as “first, second, and third lights”,respectively, the first to third lights may have different wavelengthbands. In the exemplary embodiment, the first, second, and third lightsmay correspond to blue, red, and green wavelength bands, respectively.However, the wavelength bands of the lights emitted by the pixels 111included in each pixel unit 110 should not be limited thereto orthereby, and the wavelength bands may correspond to cyan, magenta, andyellow wavelength bands. Hereinafter, a structure in which each pixelunit 110 includes the first, second, and third pixels 111 a, 111 b, and111 c that respectively emit blue, red, and green lights will bedescribed as an example.

The pixel 111 includes a light passing layer 120 provided on thesubstrate 10, the light emitting device 150 provided on the lightpassing layer 120, an insulation layer 160 provided on the lightemitting device 150, and a terminal part 170 provided on the insulationlayer 160.

The light passing layer 120 is a layer through which a light emittedfrom the light emitting device 150 passes and is provided in the pixelarea 10 d. The light passing layer 120 may be provided in each pixelarea 10 d in a one-to-one fashion. For example, when the first, second,and third pixels 111 a, 111 b, and 111 c are provided, the light passinglayer 120 is provided in every first, second, and third pixels areas 10a, 10 b, and 10 c in which the first, second, and third pixels 111 a,111 b, and 111 c are respectively provided. In FIG. 1A, the lightpassing layer 120 is shown smaller than the pixel area 10 d, however,this is just for the convenience of explanation. The light passing layer120 and the pixel area 10 d may correspond to each other and may havedifferent sizes from those shown in drawings. For instance, an area ofthe light passing layer 120 when viewed in a plan view may be slightlysmaller than, equal to, or slightly larger than an area of the pixelarea 10 d. However, the light passing layer 120 respectively provided inthe pixel areas 10 d adjacent to each other are spaced apart from eachother and do not meet or make contact with each other.

When viewed in a plan view, the light passing layer 120 is provided in ashape corresponding to a shape of the pixel area 10 d. when viewed in across section, the light passing layer 120 has a rectangular shape withan upper surface 120 p and a side surface 120 q. In the exemplaryembodiment, the upper surface 120 p may be substantially parallel to asurface of the substrate 10 disposed thereunder such that the lightemitting device 150 may be provided on the upper surface 120 p.

The light reaching the light passing layer 120 from the light emittingdevice 150 passes through the light passing layer 120 after beingincident into the light passing layer 120 and exits to the outside. Thelight passing layer 120 transmits at least a portion (e.g., at least aportion of light amount and/or at least a portion of specificwavelength) of the light from the light emitting device 150.

The light passing through the light passing layer 120 may maintain awavelength thereof when being incident into the light passing layer 120or may be converted to a light with a wavelength different from thewavelength when being incident into the light passing layer 120.

In the case where the light passing through the light passing layer 120maintains the same wavelength before and after passing through the lightpassing layer 120, the light passing layer 120 may serve as a waveguide.In the case where the light passing through the light passing layer 120have different wavelengths before and after passing through the lightpassing layer 120, the light passing layer 120 may serve as a lightconversion layer 120 f. In the present exemplary embodiment, for theconvenience of explanation, when the light passing layer 120 serves asthe light conversion layer 120 f, the light passing layer 120 will bereferred to as the “light conversion layer” 120 f and will be assignedwith a separate reference numeral. However, it should be understood thatthe light conversion layer 120 f has been explained as a componentincluded in the light passing layer 120 depending on situations.

As described above, the light conversion layer 120 f absorbs thewavelength of the light from the light emitting device 150 and emits thelight having the different wavelength. The light conversion layer 120 fabsorbs the light of relatively shorter wavelength and emits the lighthaving longer wavelength than that of the absorbed light. The lightconversion layer 120 f may selectively include materials that are ableto absorb a light having a predetermined wavelength and emit a lighthaving a different wavelength. As an example, the light conversion layer120 f may include a nano-structure such as a fluorescent substance and aquantum dot, an organic material capable of converting color, or acombination thereof. For example, when the fluorescent substance is usedas the material for the light conversion layer 120 f, the fluorescentsubstance may absorb a blue light and may emit a red light. Thefluorescent substance may be provided in a mixed form with a transparentor semi-transparent binder, such as PDMS (polydimethylsiloxane), PI(polyimide), PMMA (poly(methyl 2-methylpropenoate)), or ceramic.

The light emitting device 150 is provided on the light conversion layer120 f such that an adhesive layer 180 is disposed between the lightemitting device 150 and the light conversion layer 120 f. The adhesivelayer 180 may include a non-conductive material and may include amaterial with the light transmitting property. For instance, theadhesive layer 180 may be an optically clear adhesive (OCA). Thematerial for the adhesive layer 180 should not be particularly limitedas long as the material is optically clear and stably attaches the lightemitting device 150. The adhesive layer 180 is provided in the pixelarea 10 d corresponding to an area to which the light emitting device150 is attached and has an area corresponding to an area of the lightemitting device 150 when viewed in a plan view.

The light emitting device 150, for example, the first, second, and thirdlight emitting devices 150 a, 150 b, and 150 c are provided on the lightpassing layers, respectively, with the adhesive layer 180 therebetween.

The light emitting device 150 may be provided in each pixel 111 to emitthe lights of various wavelengths.

In the exemplary embodiment, the first, second, and third lights mayhave blue, red, and green wavelength bands. In this case, the first,second, and third light emitting devices 150 a, 150 b, and 150 c may beimplemented by a blue light emitting diode, a red light emitting diode,and a green light emitting diode. However, the first, second, and thirdlights need not have the blue, red, and green wavelength bands,respectively, to display the blue, red, and green colors. Although thefirst to third lights have the same wavelength band, the color of thelight finally emitted may be controlled by using the light conversionlayer 120 f that converts at least a portion of the first to thirdlights to a light having a different wavelength band. This is becausethe light conversion layer 120 f includes the material, such as thefluorescent substance or the quantum dot, that converts the light havingthe predetermined wavelength to the light having the differentwavelength. In other words, the first, second, and third pixels 111 a,111 b, and 111 c do not necessarily use the green, red, and blue lightemitting diodes to implement the green, red, and/or blue colors, andlight emitting diodes other than the above-mentioned color may be used.As an example, the red light emitting diode may be used to implement thered color, however, when using the light conversion layer 120 f thatabsorbs the blue light or the ultraviolet light and emit the red light,the blue or ultraviolet light emitting diode may used to implement thered color.

The light conversion layer 120 f may selectively include materials thatare able to absorb a light having a predetermined wavelength and emit alight having a different wavelength. The light conversion layer 120 fmay include the nano-structure such as the fluorescent substance and thequantum dot, an organic material capable of converting colors, or thecombination thereof. A color filter layer 130 may be further disposed ata portion adjacent to the light conversion layer 120 f to increase apurity of the color of the light finally emitted.

In the exemplary embodiment, it will be described that the first lightemitting device 150 a is green light emitting diode, the second lightemitting device is a blue light emitting diode and the third lightemitting device 150 c is a blue light emitting diode, as an example

In the exemplary embodiment, the first, second, and third light emittingdevices 150 a, 150 b, and 150 c are shown to have the same size,however, the first, second, and third light emitting devices 150 a, 150b, and 150 c may have the same size or different sizes from each other.

As shown in drawings, the first, second, and third light emittingdevices 150 a, 150 b, and 150 c are shown to have the same height,however the first, second, and third light emitting devices 150 a, 150b, and 150 c may have the same height as or different heights from eachother. According to embodiments, at least one light emitting device ofthe first, second, and third light emitting devices 150 a, 150 b, and150 c may have a different height from those of the other light emittingdevices. The height of the first, second, and third light emittingdevices 150 a, 150 b, and 150 c may vary depending on the materials andoptical characteristics of the first, second, and third light emittingdevices 150 a, 150 b, and 150 c. For example, the first light emittingdevice 150 a emitting the green light may have the height greater thanthat of the third light emitting device 150 c emitting the blue light.However, in the exemplary embodiment, although the first, second, andthird light emitting devices 150 a, 150 b, and 150 c have differentheights from each other, the heights of the first, second, and thirdlight emitting devices 150 a, 150 b, and 150 c are lower than those of aconventional light emitting device since the first, second, and thirdlight emitting devices 150 a, 150 b, and 150 c are manufactured by amanufacturing method described later and transferred onto the substrateby a transferring method described later. That is, first to third lightemitting devices used in the conventional light emitting apparatus aretransferred onto a substrate with a growth substrate when being employedin the conventional light emitting apparatus. However, since the firstto third light emitting devices used in the light emitting apparatusaccording to the exemplary embodiment are transferred right after beingseparated from the growth substrate, the heights of the light emittingdevices are lower than those of the conventional light emitting device.For instance, in the exemplary embodiment, the height from an uppersurface of the substrate to an active layer may be in a range from about2 micrometers to about 15 micrometers. As another way, in the exemplaryembodiment, the height from the upper surface of the substrate to theactive layer may be in a range from about 5 micrometers to about 10micrometers.

In the exemplary embodiment, the first, second, and third light emittingdevices 150 a, 150 b, and 150 c are provided separated from an elementsubstrate (e.g., a sapphire substrate) for growth of a semiconductorlayer. Accordingly, it is possible to thin the device. In particular, ina case of the light emitting devices emitting the green and blue lights,for example, since the first and third light emitting devices may beprovided without the sapphire substrate, a thickness of the lightemitting device may be equal to or smaller than about 15 micrometers.When the sapphire substrate is provided, the thickness of the lightemitting device has a remarkably larger value (e.g., about 50micrometers to about 100 micrometers) than that when the sapphiresubstrate is not provided. Therefore, in the exemplary embodiment, adifference in thickness between the light emitting devices depending onthe presence or absence of the element substrate may be reduced, anddefects caused by a difference in height may be prevented in thefollowing other processes described later.

The insulation layer 160 is provided on the light emitting device 150.The insulation layer 160 is provided in all the pixel area 10 d and thenon-pixel area 10 nd. The insulation layer 160 covers an upper surfaceof the light passing layer 120 and the light emitting device 150 in anarea corresponding to the pixel area 10 d. A space between the pixelarea 10 d and another pixel area 10 d is filled with the insulationlayer 160 in an area corresponding to the non-pixel area 10 nd, and theinsulation layer 160 makes contact with the upper surface of thesubstrate 10. The insulation layer 160 is provided between the lightpassing layers 120 respectively provided in the pixel areas 10 d.Accordingly, the light passing layers 120 are separated by theinsulation layer 160. Therefore, all the upper surface and the sidesurface of the light passing layer 120 are covered by the insulationlayer 160.

The insulation layer 160 includes a non-conductive material. Theinsulation layer 160 may include a material that transmits the light ora material that does not transmit the light. According to embodiments,when a color mixture occurs between the pixels 111 adjacent to eachother, the insulation layer 160 may include a non-transmitting material,and when the color mixture is required or there is no possibility ofcolor mixture, the insulation layer 160 may include a transmittingmaterial.

As the transmitting material, an organic polymer, such as epoxy,polysiloxane, or photoresist, may be used. As an example, PDMS(polydimethylsiloxane) may be used as the polysiloxane material.However, the material for the insulation layer 160 should not be limitedthereto or thereby, and materials, such as HSSQ (HydrogenSilsesquioxane), MSSQ (Methyksilsesquioxane), polyimide, DivinylSiloxane, DVS-BCS (bis-Benzocyclobutane), PFCB (Perfluorocyclobutane),and PAE (Polyarylene Ether) may be used.

The non-transmitting material may include a light absorbing material andmay include a material substantially having a light transmittance equalto or smaller than about 10%. For example, the insulation layer 160 mayhave a black color, and particularly may include a black matrix materialused in a displaying apparatus. In the present exemplary embodiment, theinsulation layer 160 may include a black photoresist and may include acarbon black. In the case where the insulation layer 160 includes theblack photoresist, the insulation layer 160 may be easily patternedusing a photolithography process. However, the material for theinsulation layer 160 should not be limited thereto or thereby, andvarious materials may be used for the insulation layer 160.

The insulation layer 160 may have a single-layer structure or amulti-layer structure. In the exemplary embodiment, the insulation layer160 may include a first insulation layer 161 provided on the substrate10 and a second insulation layer 163 provided on the first insulationlayer 161. The first insulation layer 161 may be provided on thesubstrate 10 and disposed in the non-pixel area 10 nd between the lightpassing layers 120. The second insulation layer 163 may be provided onthe light passing layer 120 and the light emitting device 150 and may beprovided in all the pixel area 10 d and the non-pixel area 10 nd. In thepresent exemplary embodiment, the first insulation layer 161 and thesecond insulation layer 163 may include the same material as ordifferent materials from each other.

A plurality contact holes is defined by partially removing theinsulation layer 160 to expose at least a portion of first and secondelectrodes 159 p and 159 q of the light emitting device 150.

The terminal part 170 is provided on the insulation layer 160 andconnected to the light emitting device 150.

The terminal part 170 may include a common pad 171 d used to apply acommon voltage to the light emitting device 150 and a data pad used toapply image signals, i.e., data signals, to the light emitting device150. The data pad includes first, second, and third data pads 171 a, 171b, and 171 c that respectively apply the data signals to the first,second, and third light emitting devices 150 a, 150 b, and 150 c.

The terminal part 170 is electrically connected to each light emittingdevice 150 through the contact hole CH defined through the insulationlayer 160. That is, the common pad 171 d and the first data pad 171 aare connected to the first light emitting device 150 a through thecontact hole CH. The common pad 171 d and the second data pad 171 b areconnected to the second light emitting device 150 b through the contacthole CH. The common pad 171 d and the third data pad 171 c are connectedto the third light emitting device 150 c through the contact hole CH.

Various types of light emitting diodes may be employed as the first,second, and third light emitting devices 150 a, 150 b, and 150 c. FIG. 2is a cross-sectional view showing the light emitting device 150according to an exemplary embodiment, and a lateral-type light emittingdiode is employed as the light emitting device 150. The light emittingdevice 150 shown in FIG. 2 may be one of the first, second, and thirdlight emitting devices 150 a, 150 b, and 150 c, and the first lightemitting device 150 a will be described as a representative example inthe present exemplary embodiment.

Referring to FIG. 2, the first light emitting device 150 a includes afirst semiconductor layer 153, an active layer 155, a secondsemiconductor layer 157, the first electrode 159 p, the second electrode159 q, the insulation layer 160, the common pad 171 d, and the firstdata pad 171 a.

In an embodiment, in a case of the light emitting device 150 that emitsthe green light, the first semiconductor layer 153, the active layer155, and the second semiconductor 157 may include indium gallium nitride(InGaN), gallium nitride (GaN), aluminum indium gallium nitride(AlInGaN), gallium phosphide (GaP), aluminum gallium indium phosphide(AlGaInP), and aluminum gallium phosphide (AlGaP). In an embodiment, ina case of the light emitting device 150 that emits the red light, thefirst semiconductor layer 153, the active layer 155, and the secondsemiconductor 157 may include aluminum gallium arsenide (AlGaAs),gallium arsenide phosphide (GaAsP), aluminum gallium indium phosphide(AlGaInP), and gallium phosphide (GaP). In an embodiment, in a case ofthe light emitting device 150 that emits the blue light, the firstsemiconductor layer 153, the active layer 155, and the secondsemiconductor 157 may include gallium nitride (GaN), indium galliumnitride (InGaN), aluminum indium gallium nitride (AlInGaN), and zincselenide (ZnSe).

In the present exemplary embodiment, the first and second semiconductorlayers may be doped with impurities of opposite types and may be ann-type or p-type semiconductor layer depending on the type of impurity.For example, the first semiconductor layer may be the n-typesemiconductor layer, and the second semiconductor layer may be thep-type semiconductor layer. On the contrary, the first semiconductorlayer may be the p-type semiconductor layer, and the secondsemiconductor layer may be the n-type semiconductor layer. In thefollowing descriptions, a configuration in which the first semiconductorlayer is the n-type semiconductor layer and the second semiconductorlayer is the p-type semiconductor layer will be described as arepresentative example.

In FIG. 2, each of the first semiconductor layer 153 and the secondsemiconductor layer 157 has the single-layer structure, howeveraccording to embodiments, each of the first semiconductor layer 153 andthe second semiconductor layer 157 may have a multi-layer structure andmay include a superlattice layer. The active layer 155 may have a singlequantum well structure or a multiple quantum well structure, and acomposition ratio of a nitride-based semiconductor of the active layer155 is controlled to emit a desired wavelength. As an example, theactive layer 155 may emit the blue light or the ultraviolet light.

The first electrode 159 p is disposed on the first semiconductor layer153 on which the active layer 155 and the second semiconductor layer 157are not provided, and the second electrode 159 q is disposed on thesecond semiconductor layer 157.

The first electrode 159 p and/or the second electrode 159 q may have asingle- or multi-layer structure of metal. The first electrode 159 pand/or the second electrode 159 q may include various metals of Al, Ti,Cr, Ni, Au, Ag, Cr, or Cu and an alloy thereof.

In the present exemplary embodiment, a plurality of concavo-convexportions may be provided on a rear surface (i.e., an opposite surface ofthe surface on which the active layer 155 is provided) of the firstsemiconductor layer 153 to increase a light emitting efficiency. Theconcavo-convex portions may be provided in various shapes, such as apolygonal pyramid, a hemisphere, or a surface having a roughness, onwhich the concavo-convex portions are randomly arranged. As an example,the rear surface of the first semiconductor layer 153 may be texturedthrough various etching processes. As another way, various shapes ofconcavo-convex portions may be formed on the first semiconductor layer153 by forming the first semiconductor layer 153 on the patternedsapphire substrate and separating the sapphire substrate.

The insulation layer 160 is provided on the first and second electrodes159 p and 159 q, and the common pad 171 d connected to the firstelectrode 159 p through the contact hole CH and the data pad 171 a areprovided on the insulation layer 160. In the present exemplaryembodiment, the first electrode 159 p is connected to the common pad 171d, and the second electrode 159 q is connected to the data pad 171 a,however this is for the convenience of explanation, and they should notbe limited thereto or thereby. For example, the first data pad 171 a maybe connected to the first electrode 159 p, and the common pad 171 d maybe connected to the second electrode 159 q.

The common pad 171 d and/or the first data pad 171 a may include asingle- or multi-layer of metal. The common pad 171 d and/or the firstdata pad 171 a may include various metals of Al, Ti, Cr, Ni, or Au andan alloy thereof.

In the exemplary embodiment, the light emitting device 150 is roughlydescribed with reference to drawings. The light emitting device 150 mayfurther include a layer with additional functionality in addition to theabove-mentioned layers. For instance, various layers, such as areflection layer that reflects the light, an additional insulation layerthat insulates specific components, and a solder prevention layer thatprevents a solder from being diffused, may be included in the lightemitting device 150.

In addition, when the lateral-type light emitting device is formed, amesa may be formed in various shapes, and locations and shapes of thefirst and second electrodes may be changed in various ways.

According to the light emitting apparatus of the exemplary embodiment,the light emitting device 150 is turned on in response to the commonvoltage and the data signal applied thereto to emit the light, and theemitted light travels to the rear surface of the substrate 10 afterpassing through the substrate 10 thereunder.

According to the light emitting apparatus of the exemplary embodiment,since the pixels and the terminal part are sequentially formed on thesubstrate, the light emitting apparatus may be manufactured withoutusing a separate printed circuit board. In a case where the lightemitting apparatus is manufactured by mounting the light emitting deviceon the separate printed circuit board, a process for forming aconductive electrode on the printed circuit board and/or a process forconnecting a wire are required. However, the forming and connectingprocesses may be omitted in the exemplary embodiment. The manufacturingmethod of the displaying apparatus will be described later.

According to the light emitting apparatus of the above-describedembodiment, the manufacturing process is simplified, and color purityand color reproducibility are also improved.

In a conventional displaying apparatus, when a pixel is formed bymounting a light emitting apparatus on a substrate, the light emittingapparatus is mounted on a transparent insulation layer formed on thesubstrate. In a case where the insulation layer used on the substrate istransparent, the transparent insulation layer is used as a waveguide,and thus there is a problem in which a light is propagated from onepixel to another pixel adjacent to the one pixel. However, according tothe exemplary embodiment, since the insulation layer that does nottransmit the light is provided in each pixel area 10 d, the insulationlayer is not used as the waveguide. In particular, the insulation layermay be provided to have the black color, and thus the light may beprevented from traveling to adjacent pixels. Accordingly, the colormixture or a light interference between the pixels adjacent to eachother may be prevented, and the final color purity and colorreproducibility may be improved

In addition, since the area displayed in the black color increases, acontrast ratio between the black area and the light emitted from eachlight emitting apparatus increases, and characteristics of thedisplaying apparatus is improved.

Further, according to the exemplary embodiment, a color filter layer ora color filter part may be additionally used in addition to the lightconversion layer. Therefore, the color purity and the colorreproducibility may be further improved. The light that is notcompletely converted by the light conversion layer or the lighttraveling from the adjacent pixel are blocked once again by the colorfilter layer or the color filter part.

According to the exemplary embodiment, the light emitting apparatus mayhave various configurations without departing from the inventiveconcepts.

FIG. 3 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment, which is taken along a line I-I′of FIG. 1A. In the following embodiments, different features from thoseof the above-described embodiments will be mainly described in order toavoid redundancy. Unexplained portions are similar to those of theabove-described embodiments.

Referring to FIG. 3, an insulation layer 160 may be formed in a waydifferent from that of the above-described embodiments to prevent thecolor mixture between the pixels 111 adjacent to each other. Theinsulation layer 160 according to the exemplary embodiment may have astructure that blocks the light as much as possible to prevent the colormixture between the pixels 111 adjacent to each other. To this end, afirst insulation layer 161 may include a first sub-insulation layer 161p and a second sub-insulation layer 161 q completely covering the firstsub-insulation layer 161 p.

The first sub-insulation layer 161 p may be provided on a substrate 10to directly make contact with the substrate 10, and a side surface andan upper surface of the first sub-insulation layer 161 p may becompletely covered by the second sub-insulation layer 161 q. As anotherway, the first sub-insulation layer 161 p may be provided at the sameheight as a light passing layer 120, and in this case, the upper surfaceof the first sub-insulation layer 161 p may be covered by a secondinsulation layer 163.

The first sub-insulation layer 161 p may be provided as a whiteinsulation layer 160. The second sub-insulation layer 161 q may beprovided as a black insulation layer 160. When the white insulationlayer 160 and the black insulation layer 160 are combined with eachother, most of the wavelength bands, particularly, most of the light inthe visible light band, which is emitted from one pixel, may beprevented from traveling to other pixels 111 adjacent to each other.

In the present exemplary embodiment, the first sub-insulation layer 161p may include an insulating material having the white color, such as anorganic polymer or an organic-inorganic composite material. The secondsub-insulation layer 161 q may include a non-light transmitting materialas the second insulation layer 163 and may include the same material asthe second insulation layer 163.

The light emitting apparatus according to the exemplary embodiment mayfurther include various additional components to improve the lightemitting efficiency.

FIG. 4 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 4, a diffusion plate 191 is disposed on a rear surfaceof a substrate 10. The diffusion plate 191 diffuses the light emittingfrom each pixel 111 to prevent a dark dot or a bright dot. Since a lightemitting device 150 or a light emitting area of the light emittingdevice 150 is smaller in size than the pixel 111, the dark dot or thebright dot may appear due to a difference in contrast between a portioncorresponding to the light emitting area and a portion not correspondingto the light emitting area. In the present exemplary embodiment, sincethe diffusion plate 191 is disposed on the rear surface of the substrate10 to which the light travels, the light may be properly diffused ineach pixel 111, and thus the light may be uniformly emitted withoutcausing the dark or bright dot.

In the exemplary embodiment, the diffusion plate 191 is described as arepresentative example, however various optical sheets for improving thelight efficiency may be further disposed on the rear surface of thesubstrate 10. For example, a prism sheet for linearity of light and/or afilter for blocking or transmitting a light having a specific wavelengthmay be further disposed on the rear surface of the substrate 10. Theoptical sheets may be arranged in various orders depending on desiredfunctions.

The light emitting apparatus according to the exemplary embodiment mayfurther include additional components to improve the light emittingefficiency and prevent the color mixture of the light between pixelsadjacent to each other.

FIG. 5 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 5, a reflection layer 140 is provided on a sidesurface of a light passing layer 120. In detail, the reflection layer140 may be provided between an insulation layer 160, particularly, afirst insulation layer 161 and the side surface of the light passinglayer 120. The reflection layer 140 may be also provided even though thelight passing layer 120 is used as a light conversion layer 120 f.

The reflection layer 140 may include a conductive or non-conductivematerial that reflects the light emitted from the light emitting device150. As the conductive material, a metal or metal alloy may be used, andas the non-conductive material, an organic-inorganic composite materialor a dielectric mirror may be used.

The metal or metal alloy may include a metal material with highreflectance, e.g., silver, aluminum, copper, platinum, and gold.

The organic-inorganic composite material may be provided in the form ofan inorganic filler having a small particle diameter mixed with apolymer resin. The inorganic filler may include barium sulfate, calciumsulfate, magnesium sulfate, barium carbonate, calcium carbonate,magnesium chloride, aluminum hydroxide, magnesium hydroxide, calciumhydroxide, titanium dioxide, alumina, silica, talc, or zeolite, howeverit should not be limited thereto or thereby.

The dielectric mirror may have a structure in which insulation layershaving different refractive indices from each other are stacked one onanother. A material for the dielectric mirror should not be particularlylimited, and various organic or inorganic materials may be used as thedielectric mirror.

In the exemplary embodiment, the material and structure of thereflection layer 140 may be determined in accordance with the wavelengthband of the light emitted from the light emitting device 150 of thecorresponding pixel 111. Since specific materials or metals havedifferent reflectances depending on the wavelength, it is advantageousto select the material of the reflection layer 140 among materials withhigh reflectance in the wavelength band of the light from the lightemitting device 150. As an example, in a case where the light emittingdevice 150 emits a light having an ultraviolet wavelength band, aluminumor an aluminum alloy having high reflectance in the ultravioletwavelength band may be selected as the material for the reflection layer140, and the reflectance of the dielectric mirror in the ultravioletwavelength band may increase by adjusting the material or the number ofstacked layers.

In the present exemplary embodiment, the reflection layer 140 providedbetween the first insulation layer 161 and the side surface 120 q of thelight passing layer 120 is described, however it should not be limitedthereto or thereby. According to another embodiment, the reflectionlayer 140 may be also provided on the upper surface 120 p of the lightpassing layer 120, i.e., between the light passing layer 120 and thesecond insulation layer 163. However, in a case where the reflectionlayer 140 includes the conductive material such as the metal material,the reflection layer 140 is provided in an insulated state not to beelectrically connected to a terminal part 170 of the light emittingdevice 150.

According to the exemplary embodiment, the light emitted from the lightemitting device 150 travels through the corresponding light passinglayer 120 by the reflection layer 140 and the traveling of the light tothe adjacent pixels 111 is prevented as much as possible. As a result,the color mixture in which the light from the specific pixel 111 ismixed with the light from the adjacent pixels 111 may be prevented.

The light emitting apparatus according to the exemplary embodiment mayimplement the color light using various light emitting devices havingdifferent wavelength from the above-mentioned embodiment and the lightconversion layer corresponding to the light emitting devices.

FIG. 6 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 6, in the light emitting apparatus according to theexemplary embodiment, all light emitting devices 150 may emit a lighthaving ultraviolet wavelength band, and a light passing layer 120 may beprovided as a light conversion layer 120 f that converts an ultravioletlight to a light having a specific color.

In the present exemplary embodiment, first, second, and third lightemitting devices 150 a, 150 b, and 150 c respectively provided in first,second, and third pixels 111 a, 111 b, and 111 c may emit theultraviolet light, and the light conversion layer 120 f is provided inall the first pixel 111 a to the third pixel 111 c. Accordingly, thelight conversion layer 120 f of the first pixel 111 a may include alight conversion material that converts the ultraviolet light emittedfrom the first light emitting device 150 a to a blue light, the lightconversion layer 120 f of the second pixel 111 b may include a lightconversion material that converts the ultraviolet light emitted from thesecond light emitting device 150 b to a red light, and the lightconversion layer 120 f of the third pixel 111 c may include a lightconversion material that converts the ultraviolet light emitted from thethird light emitting device 150 c to a green light.

The light conversion material may include a nano-structure such as afluorescent substance and a quantum dot, an organic material capable ofconverting colors, or a combination thereof and may be selecteddepending on desired colors.

In the present exemplary embodiment, a color filter part CF may befurther provided between a substrate 10 and the light passing layer 120.The color filter part CF may include color filters B, R, and G providedin a pixel area 10 d corresponding to each pixel 111 and a black matrixBM provided corresponding to a non-pixel area 10 nd. The color filtersB, R, and G may be provided corresponding to the color of each pixel 111and may include a blue color filter B, a red color filter R, and a greencolor filter G.

The color filters B, R, and G may improve the color purity of the lightconverted by each light conversion layer 120 f and may substantiallysimultaneously block the light that is not converted among the lightsemitted from the light emitting device 150. In particular, in the casewhere the light emitting device 150 emits the ultraviolet light, aportion of the ultraviolet light may not be converted to the specificcolor, such as blue, red, and green colors, and the color filter mayblock the ultraviolet light that is not converted.

The light emitting apparatus according to an exemplary embodiment mayimplement the color light using various light emitting devices havingdifferent wavelength from that in the exemplary embodiment of FIG. 6 andthe light conversion layer corresponding to the light emitting devices.

FIG. 7 is a cross-sectional view showing a light emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 7, in the light emitting apparatus according to theexemplary embodiment, all light emitting devices 150 may emit a lighthaving blue wavelength band, and a light passing layer 120 may beprovided as a light conversion layer 120 f that converts the blue colorto a specific color in some pixels 111.

In the present exemplary embodiment, first, second, and third lightemitting devices 150 a, 150 b, and 150 c respectively provided in first,second, and third pixels 111 a, 111 b, and 111 c may emit the bluelight. Accordingly, the first pixel 111 a corresponding to the bluepixel 111 does not need the light conversion, and the light passinglayer 120 that transmits all the lights emitted from the light emittingdevice 150 is provided. Since the second pixel 111 b and the third pixel111 c need the light conversion, the light conversion layer 120 f isprovided in the second pixel 111 b and the third pixel 111 c. That is,the light conversion layer 120 f of the second pixel 111 b may include alight conversion material that converts the blue light emitted from thesecond light emitting device 150 b to the red light, and the lightconversion layer 120 f of the third pixel 111 c may include a lightconversion material that converts the blue light emitted from the thirdlight emitting device 150 c to the green light.

The light conversion material may include a nano-structure such as afluorescent substance and a quantum dot, an organic material capable ofconverting colors, or a combination thereof and may be selecteddepending on desired colors.

In the present exemplary embodiment, a color filter part CF may befurther provided between a substrate 10 and the light passing layer 120.However, since the blue light is emitted from the light emitting device150 in the case of the first pixel 111 a, a blue color filter thatadditionally blocks ultraviolet light is not required. Accordingly, theblue color filter may be omitted with respect to the first pixel 111 a,and a transparent insulation layer T may be provided in the first pixel111 a. On the other hand, since there may be the blue light that is notcompletely converted by the light conversion layer 120 f in the secondand third pixels 111 b and 111 c, a red color filter R and a green colorfilter G may be respectively provided in the pixel areas 10 d to blockthe blue light that is not completely converted.

In the above-described embodiments, the configuration in which at leastone light passing layer among the light passing layers is the lightconversion layer is described, however according to the exemplaryembodiment, the light emitting apparatus may be manufactured withoutemploying the light conversion layer.

FIGS. 8A and 8B are cross-sectional views showing a light emittingapparatus according to an exemplary embodiment. FIGS. 8A and 8B show alight emitting apparatus employing a lateral-type light emitting deviceand a light emitting apparatus employing vertical-type light emittingdevice without the light conversion layer.

Referring to FIG. 8A, the first, second, and third light emittingdevices 150 a, 150 b, and 150 c may emit blue, red, and green lights,respectively. To this end, the first, second, and third light emittingdevices 150 a, 150 b, and 150 c may be manufactured by selecting any oneof semiconductor materials that respectively emit the blue, red, andgreen lights.

For example, in an embodiment, the first light emitting device 150 a mayinclude gallium nitride (GaN), indium gallium nitride (InGaN), aluminumindium gallium nitride (AlInGaN), and zinc selenide (ZnSe), andparticularly may include aluminum indium gallium nitride (AlInGaN).

In an embodiment, the second light emitting device 150 b may includealuminum gallium arsenide (AlGaAs), gallium arsenide phosphide (GaAsP),aluminum gallium indium phosphide (AlGaInP), and gallium phosphide(GaP), and particularly may include aluminum gallium indium phosphide(AlGaInP).

In an embodiment, the third light emitting device 150 c may includeindium gallium nitride (InGaN), gallium nitride (GaN), aluminum indiumgallium nitride (AlInGaN), and zinc selenide (ZnSe), and particularlymay include aluminum indium gallium nitride (AlInGaN).

In the present exemplary embodiment, since each of the first, second,and third light emitting devices 150 a, 150 b, and 150 c emits the colorlight having the specific wavelength, no separate light conversion layeris required, and the light emitting apparatus may be manufactured in arelatively simple manner.

Referring to FIG. 8B, not only the lateral-type light emitting devicebut also the vertical-type light emitting device may be used as thefirst, second, and third light emitting devices 150 a, 150 b, and 150 c.In the exemplary embodiment, the vertical-type light emitting device maybe used as the second light emitting device 150 b that emits the redlight. The second light emitting device 150 b may include asemiconductor layer that emits the red light and may include, forexample, aluminum gallium indium phosphide (AlGaInP).

In the present exemplary embodiment, first and second electrodes of thesecond light emitting device 150 b may be respectively provided on upperand lower side surfaces, and each of the first and second electrodes maybe electrically connected to a common pad 171 d or a second data pad 171b through a contact hole. In the exemplary embodiment, the vertical-typelight emitting device has an advantage of occupying less area than thelateral-type light emitting device when viewed in a plan view, and thusthe vertical-type light emitting devices can be formed in a higherdensity than the lateral-type light emitting devices.

As described above, according to the exemplary embodiment, when thelight emitting device that emits the light having the specific color ismanufactured, it is possible to select the type of the light emittingdevice that is relatively easy to manufacture among the vertical-type orthe lateral-type in accordance with the substrate or material used.

It has been previously described that the lateral or vertical typedevices are used, but a light emitting device is not limited to thesetype devices.

The light emitting apparatus according to the exemplary embodiment maybe employed in various apparatuses and, for example, may be employed ina backlight unit used in the displaying apparatus.

FIG. 9A is a plan view showing a light emitting apparatus includinglight emitting devices connected to each other in parallel according toan exemplary embodiment, and FIG. 9B is a cross-sectional view takenalong a line II-IF of FIG. 9A. FIG. 10 is a plan view showing a lightemitting apparatus including light emitting devices connected to eachother in series according to an exemplary embodiment. In the presentexemplary embodiment, the light emitting apparatus may havesubstantially the same structure as the pixel unit 110 in theabove-described embodiment, and thus, for the convenience ofexplanation, a light emitting unit in which one light emitting device150 is provided will be referred to as a “pixel” 111 similar to theabove-described embodiments.

Referring to the above-described embodiments and FIGS. 9A and 9B, thelight emitting apparatus includes the substrate 10 and the pixel 111mounted on the substrate 10. Each pixel 111 includes the substrate 10,the light passing layer 120 provided on the substrate 10, the lightemitting device 150 provided on the light passing layer 120, theinsulation layer 160 covering the light emitting device 150 and thelight passing layer 120, and the terminal part 170 provided on theinsulation layer 160.

In the present exemplary embodiment, the terminal part 170 includes thecommon pad 171 p used to apply the common voltage to one electrode ofthe first and second electrodes of the light emitting device 150 and thedata pad 171 q used to apply the light emitting signal to the otherelectrode of the first and second electrodes. The common pad 171 p andthe data pad 171 q may be spaced apart from each other and may extend inone direction. One electrode of the first and second electrodes of eachlight emitting device 150 may be connected to the common pad 171 pthrough the contact hole CH, and the other electrode of the first andsecond electrodes of each light emitting device 150 may be connected tothe data pad 171 q through the contact hole CH. Consequently, each lightemitting device 150 is connected in parallel between the common pad 171p and the data pad 171 q.

FIG. 10 is a plan view showing a light emitting apparatus including alight emitting device 150 connected in series according to an exemplaryembodiment. There is no big difference between the light emittingapparatus shown in FIG. 10 and the light emitting apparatus shown inFIG. 9A except that a shape of the terminal part 170 of FIG. 10 ispartially different from that of FIG. 9A and a connection relation ofboth ends at which the common pad 171 p and the data pad 171 q of thelight emitting device 150 are provided of FIG. 10 is different from thatof FIG. 9A, and thus details thereof will be omitted.

The light emitting apparatus having the above-mentioned structureaccording to the exemplary embodiments may be manufactured by preparingthe substrate and sequentially forming components on the substrate. Inparticular, the light emitting apparatus may be manufactured throughpreparing light emitting devices and transferring the light emittingdevices to a substrate.

Hereinafter, a method of forming and transferring light emitting devicesis first described in sequence, and then a light emitting apparatus willbe described.

FIG. 11 is a flowchart showing the transferring method aftermanufacturing the light emitting device in the manufacturing method ofthe light emitting apparatus according to an exemplary embodiment. Thelight emitting device manufactured in the following embodiment may usethe gallium nitride (GaN) semiconductor and may be the blue lightemitting device or the green light emitting device.

Referring to FIG. 11, the manufacturing and transferring method of thelight emitting device according to the exemplary embodiment includesforming a gallium nitride (GaN) semiconductor layer on a temporarysubstrate S10, manufacturing the light emitting device by forming anelectrode part on the semiconductor layer S20, forming a protectivelayer on the manufactured light emitting device S30, irradiating a laserto an interface between the temporary substrate and the semiconductorlayer S40, removing the protective layer S50, and transferring the lightemitting device onto the substrate using a conveying apparatus S60.

FIGS. 12A to 12N are cross-sectional views showing in detail themanufacturing and transferring method of the light emitting device inorder.

Referring to FIG. 12A, an epitaxial stack is formed on a first temporarysubstrate 10 p. The epitaxial stack may include a semiconductor layerincluding the first semiconductor layer 153, the active layer 155, andthe second semiconductor layer 157. In the exemplary embodiment, thefirst temporary substrate 10 p may be a sapphire substrate. Thesemiconductor layer may be the gallium nitride (GaN) semiconductorlayer. For instance, the first semiconductor layer 153, the active layer155, and the second semiconductor layer 157 may be an n-type galliumnitride (GaN) semiconductor layer, an aluminum indium gallium nitride(AlInGaN) semiconductor layer, and a p-type gallium nitride (GaN)semiconductor layer, respectively.

Referring to FIG. 12B, the epitaxial stack formed on the first temporarysubstrate 10 p is isolated into each light emitting device unit. Eachlight emitting device unit is a minimum unit required to manufacture onelight emitting device, and the light emitting devices adjacent to eachother are physically separated.

Referring to FIG. 12C. a mesa structure is formed in the epitaxial stackcorresponding to each light emitting device. That is, the epitaxialstack has the mesa structure in which some portions are protruded upwardand the other portions are recessed downward. To this end, some portionsof the first semiconductor layer 153, the active layer 155, and thesecond semiconductor layer 157 among layers of the epitaxial stack areremoved, and thus the first semiconductor 153 is exposed upward. In theexemplary embodiment, portions of the n-type semiconductor layer, theactive layer, and the p-type semiconductor layer are removed, and thusthe n-type semiconductor layer may be exposed upward.

Referring to FIG. 12D, the electrode part is formed on the epitaxialstack manufactured on the first temporary substrate 10 p, and thus thelight emitting device is manufactured. The electrode part includes thefirst electrode 159 p connected to the first semiconductor layer 153 andthe second electrode 159 q connected to the second semiconductor layer157. The first electrode 159 p is formed on the first semiconductorlayer 153 on which the active layer 155 and the second semiconductorlayer 157 are not provided, and the second electrode 159 q is formed onthe second semiconductor layer 157. The first and/or second electrodes159 p and 159 q may have a single- or multi-layer structure of the metalmaterial.

Referring to FIG. 12E, the protective layer 165 is formed on the lightemitting device 150 manufactured on the first temporary substrate 10 p.The protective layer 165 is used to temporarily protect the lightemitting device in the manufacturing process of the light emittingdevice. Accordingly, the protective layer 165 may be formed of amaterial that is easily removed after being formed to completely coverthe light emitting device 150. The material for the protective layer 165should not be particularly limited and may include, for example,organic/inorganic polymers, such as epoxy, polysiloxane, or photoresist.As an example, PDMS (polydimethylsiloxane) may be used as thepolysiloxane material. However, the material for the protective layer165 should not be particularly limited, and materials, such as HSSQ(Hydrogen Silsesquioxane), MSSQ (Methyksilsesquioxane), polyimide,Divinyl Siloxane, DVS-BCS (bis-Benzocyclobutane), PFCB(Perfluorocyclobutane), and PAE (Polyarylene Ether), may be used as thematerial of the protective layer 165.

Referring to FIG. 12F, a second temporary substrate 10 q is providedabove the protective layer 165 with a separation layer 10 q′ interposedtherebetween. The second temporary substrate 10 q is a support substrateto support each light emitting device 150 and the protective layer 165from above. The separation layer 10 q′ attaches the second temporarysubstrate 10 q to the protective layer 165 but is used to easilyseparate the second temporary substrate 10 q from the protective layer165.

In the exemplary embodiment, the second temporary substrate 10 q may bea sapphire substrate, and the separation layer 10 q′ may include a metaloxide material, such as indium tin oxide (ITO). However, the secondtemporary substrate 10 q and the separation layer 10 q′ should not belimited thereto or thereby. That is, the second temporary substrate 10 qand the separation layer 10 q′ may include various materials as long asthey sufficiently support the protective layer 165 and the lightemitting devices 150 in the protective layer 165 and are easily removed.

In the present exemplary embodiment, the laser LSR is irradiated to theinterface between the light emitting devices 150 and the first temporarysubstrate 10 p while the light emitting devices 150 and the protectivelayer 165 are supported by the second temporary substrate 10 q. Indetail, the laser LSR is irradiated to the interface between the firstsemiconductor layer 153 and the first temporary substrate 10 p.

The laser LSR is used to pyrolyze molecules in the interface between thefirst semiconductor layer 153 and the first temporary substrate 10 p. Inthe exemplary embodiment, the first semiconductor layer 153 includesgallium nitride (GaN), the gallium nitride (GaN) is pyrolyzed by theirradiation of the laser LSR, and as a result, nitrogen atoms areremoved as nitrogen gas (N₂). Accordingly, an auxiliary layer 151containing gallium (Ga) is formed between the first semiconductor layer153 and the first temporary substrate 10 p after removing nitride (N)from the gallium nitride (GaN). In this case, since the gallium (Ga)still remains between the first semiconductor layer 153 and the firsttemporary substrate 10 p, the light emitting device is continuouslyattached onto the substrate due to an adhesion of the gallium (Ga).However, the adhesion between the first semiconductor layer 153 and thefirst temporary substrate 10 p after irradiating the laser LSR ismarkedly weakened when compared with the adhesion between the firstsemiconductor layer 153 and the first temporary substrate 10 p beforeirradiating the laser LSR.

The second temporary substrate 10 q prevents the light emitting device150 and the protective layer 165 from being lifted when the laser LSR isirradiated to the interface between the first semiconductor layer 153and the first temporary substrate 10 p. The light emitting device 150and/or the protective layer 165 adjacent to the light emitting device150 may be lifted due to heat and gas generated when the laser LSR isirradiated, however, since the second temporary substrate 10 q supportsthe light emitting devices 150 and the protective layer 165 whiledownwardly pressing the light emitting devices 150 and the protectivelayer 165, the lift of the light emitting devices 150 and the protectivelayer 165 may be minimized.

Referring to FIG. 12G, the laser LSR is irradiated between the secondtemporary substrate 10 q and the protective layer 165, in detail, to theseparation layer 10 q′ provided between the second temporary substrate10 q and the protective layer 165.

Referring to FIG. 12H, when the laser LSR is irradiated to theseparation layer 10 q′, the adhesion between the second temporarysubstrate 10 q and the protective layer 165 is weakened, and thus thesecond temporary substrate 10 q is easily removed.

Referring to FIG. 12I, the protective layer 165 is removed. Theprotective layer 165 may be easily removed using a wet or dry etchingprocess. Accordingly, the light emitting device 150 is finally formed onthe first temporary substrate 10 p, and the auxiliary layer 151 havingweak adhesion is formed between the first temporary substrate 10 p andthe first semiconductor layer 153 of the light emitting device 150.

Referring to FIG. 12J, the conveying apparatus 190 is disposed above thelight emitting device 150 to be conveyed. A temporary adhesive layer 181is provided on a surface of the conveying apparatus 190, which faces thelight emitting device 150. Since the temporary adhesive layer 181 isprovided only to areas corresponding to the light emitting devices 150to be conveyed, locations of the temporary adhesive layer 181 may bedetermined by taking into account final locations of the light emittingdevices 150 to be conveyed.

Referring to FIG. 12K, the light emitting device 150 is attached to thetemporary adhesive layer 181 by making contact the temporary adhesivelayer 181 of the conveying apparatus 190 with the light emitting device150.

Referring to FIG. 12L, the conveying apparatus 190 moves spaced apartfrom the first temporary substrate 10 p while the light emitting device150 is attached to the temporary adhesive layer 181. Due to the movementof the conveying apparatus 190, the light emitting device 150 attachedto the temporary adhesive layer 181 is separated from the firsttemporary substrate 10 p. In this case, the adhesion of the temporaryadhesive layer 181 is larger than the adhesion of the auxiliary layer151 including gallium (Ga). Since the adhesion of the auxiliary layer151 including gallium (Ga) is very weak, the light emitting device 150is very easily separated from the first temporary substrate 10 p byusing the temporary adhesive layer 181.

Referring to FIG. 12M, a substrate on which the light emitting device150 is finally mounted is prepared, and the adhesive layer 180 isprovided on the substrate to attach the light emitting device 150. InFIG. 7M, for the convenience of explanation, some components areomitted, and other components are not disposed on the substrate 10 andthe adhesive layer 180. However, various components of the displayingapparatus, e.g., the light passing layer, the light conversion layer, orthe reflection layer, may be further interposed between the substrate 10and the adhesive layer 180.

In the exemplary embodiment, the light emitting devices 150 attached tothe conveying apparatus 190 are aligned on and attached to the substrate10 on which the adhesive layer 180 is formed. In this case, anattachment area between the light emitting device 150 and the adhesivelayer 180 may be wider than an attachment area between the lightemitting devices 150 and the temporary adhesive layer 181 on theconveying apparatus 190.

Referring to FIG. 12N, the conveying apparatus 190 is separated from thefirst light emitting device 150 after the light emitting devices 150 areattached to the adhesive layer 180. Although the temporary adhesivelayer 181 on the conveying apparatus 190 has substantially the sameadhesion as that of the adhesive layer 180 on the substrate 10, theconveying apparatus 190 (in detail, the temporary adhesive layer 181 onthe conveying apparatus 190) may be easily separated from the lightemitting devices 150 since the adhesion between the light emittingdevice 150 and the adhesive layer 180 is high when the attachment areabetween the light emitting device 150 and the adhesive layer 180 iswider than the attachment area between the light emitting device 150 andthe temporary adhesive layer 181 on the conveying apparatus 190.

As described above, according to the exemplary embodiment, the lightemitting device formed on the separate substrate may be easilytransferred on the desired substrate. In more detail, according to theexemplary embodiment, it is possible to form the epitaxial stack on thegrowth substrate, such as the sapphire substrate, and to directlytransfer the light emitting device from the growth substrate onto thesubstrate, on which the light emitting device is to be formed. Inaddition, since it is possible to precisely and selectively align onlythe light emitting devices corresponding to desired locations on thesubstrate using the conveying apparatus after forming the light emittingdevices on the growth substrate, such as the sapphire substrate, defectscaused by misalignment of the light emitting devices in themanufacturing process of the light emitting apparatus are reduced.Further, since it is possible to directly transfer the light emittingdevice without additional processes, a polishing or breaking process isnot needed. Therefore, the manufacturing process of the light emittingapparatus may be simplified, a production yield of the light emittingapparatus may increase, and a manufacturing cost of the light emittingdevice may be reduced.

In addition, although not shown in drawings, the light emitting devicethat does not use the gallium nitride (GaN) semiconductor, e.g., the redlight emitting device, may be transferred onto the substrate after beingmanufactured in various ways other than the above-described method. Inthe exemplary embodiment, the method of manufacturing and transferringthe red light emitting device on the gallium arsenide (GaAs)semiconductor substrate may be performed by forming a sacrificial layeron the gallium arsenide (GaAs) semiconductor substrate, forming aluminumgallium indium phosphide (AlGaInP) semiconductor layer on thesacrificial layer, forming the electrode part on the semiconductor layerto manufacture the red light emitting device, removing the sacrificiallayer, and conveying the red light emitting device onto the substrateusing the conveying apparatus.

In the exemplary embodiment, the light emitting device may bemanufactured and transferred as described in FIGS. 12A to 12N, howeveraccording to another embodiment, other types of light emitting devicemay be manufactured and transferred using other types of substrates. Forexample, a light emitting device provided with concavo-convex portionsformed on a lower portion thereof may be manufactured using a patternedsubstrate provided with predetermined concavo-convex portions formed onan upper portion thereof and may be transferred onto the substrate.

FIGS. 13A to 13E are cross-sectional views showing a manufacturingmethod of a light emitting device and a transferring method of the lightemitting device according to another exemplary embodiment. For theconvenience of explanation, only the main processes are illustrated inFIGS. 8A to 8E. In the exemplary embodiment shown in FIGS. 13A to 13E,the manufacturing and transferring method of the light emitting deviceare substantially the same as those of the embodiment shown in FIGS. 12Ato 12N except for the patterned substrate, i.e., a patterned sapphiresubstrate (PSS), used as a first temporary substrate 10 p. Accordingly,hereinafter, different features from those of the above-describedembodiments will be mainly described in order to avoid redundancy.

Referring to FIG. 13A, the patterned first temporary substrate 10 p isprovided as the first temporary substrate 10 p, and an epitaxial stackincluding a first semiconductor layer 153, an active layer 155, and asecond semiconductor layer 157 is formed on the patterned firsttemporary substrate 10 p.

The patterned first temporary substrate 10 p has the concavo-convexportions PR, and each concavo-convex portion PR may be provided invarious shapes, such as a polygonal pyramid, a hemisphere, or a surfacehaving a roughness, on which the concavo-convex portions are randomlyarranged. In FIG. 13A, for the convenience of explanation, the uppersurface of the first temporary substrate 10 p has semi-circular convexportions in cross-section as a representative example.

Referring to FIG. 13B, light emitting devices 150 are formed on thefirst temporary substrate 10 p through separating and etching processesof the epitaxial stack and forming of an electrode part.

Referring to FIG. 13C, a laser LSR is irradiated to an interface betweenthe first semiconductor layer 153 and the first temporary substrate 10 pto form an auxiliary layer 151. In this case, since the auxiliary layer151 is formed along an upper surface of the first temporary substrate 10p, the auxiliary layer 151 has substantially the same shape as that ofthe concavo-convex portions PR.

Referring to FIG. 13D, the light emitting device 150 is separated fromthe first temporary substrate 10 p using a conveying apparatus 190. Inthis case, a lower surface of the light emitting device 150 has a shapecorresponding to the upper surface of the patterned first temporarysubstrate 10 p. That is, the lower surface of the light emitting device150 has a reverse shape of the concavo-convex portions PR on the uppersurface of the first temporary substrate 10 p, and thus theconcavo-convex portions PR are formed on the lower surface of the lightemitting device 150.

Referring to FIG. 13E, the light emitting device 150 including theconcavo-convex portions PR formed on the lower surface thereof isattached to a substrate 10 with an adhesive layer 180 interposedtherebetween.

As described above, when the concavo-convex portions are formed in thelight emitting device, the light emitting efficiency increases. Theremay be a difference in intensity between lights emitted from the lightemitting devices, and the difference in intensity may cause a differencein visibility. Accordingly, the concavo-convex portions may beselectively formed in the light emitting device in accordance with thelight emitting efficiency.

In the exemplary embodiments, the light emitting apparatuses accordingto the above-described embodiments may be manufactured throughsubstantially the same method with some structural differences.Hereinafter, a method of manufacturing the light emitting apparatusshown in FIGS. 1A and 1B using the manufacturing and transferringmethods of the light emitting device shown in FIGS. 11 to 13 will bedescribed. The manufacturing and transferring methods of the lightemitting device shown in FIGS. 11 to 13 may be employed in operations oftransferring the light emitting device onto the substrate on which thelight passing layer (and/or the light conversion layer) and the colorfilter layer are formed after the light passing layer (and/or the lightconversion layer) and a color filter layer are formed on the substrate,and thus the manufacturing and transferring methods of the lightemitting device will be described with the operations of forming thelight passing layer and the color filter layer on the substrate. In thefollowing embodiments, for the convenience of explanation, somecomponents are omitted, and some components are shown. Unexplainedportions are assumed to be the same as or similar to those of theabove-described embodiments.

FIGS. 14A to 14M are cross-sectional views showing a manufacturingmethod of the light emitting apparatus according to an exemplaryembodiment.

Referring to FIG. 14A, the substrate 10 is prepared, the firstinsulation layer 161 is formed on the substrate 10. The first insulationlayer 161 may be formed through various methods. As an example, thefirst insulation layer 161 may be formed by coating an insulatingmaterial on the substrate 10 and patterning the insulating materialusing a photolithography process.

Referring to FIG. 14B, a photoresist is coated on the substrate 10 onwhich the first insulation layer 161 is formed, and the photoresist isexposed and developed to form a first photoresist pattern PR1. Here, anarea from which the photoresist is removed corresponds to the area inwhich the light conversion layer 120 f is formed, and in the presentexemplary embodiment, the area corresponds to a second pixel area.

Referring to FIG. 14C, the color filter layer 130 is selectively formedin the second pixel area in which the first photoresist pattern PR1 isnot formed. The color filter layer 130 may be formed by a spin coatingmethod, a screen printing method, or the like. The color filter layer130 may be formed on an entire surface of the substrate 10 on which thefirst photoresist pattern PR1 is formed or formed by patterning thecolor filter layer 130 formed on the entire surface of the substrate 10.Although the color filter layer 130 is formed on the entire surface ofthe substrate 10, the color filter layer 130 may not be patterned sincethe color filter layer 130 may be partially removed by a polishingprocess described later.

In the drawings according to the present exemplary embodiment, a processof forming the reflection layer is not shown, however the reflectionlayer may be further formed on the substrate 10, on which the firstinsulation layer 161 is formed, before the color filter layer 130 isformed. The reflection layer may be formed, for example, by forming themetal layer or the dielectric mirror layer and patterning the metallayer or the dielectric mirror layer using a photolithography process.

Referring to FIG. 14D, the light conversion layer 120 f is formed in thesecond pixel area in which the first photoresist pattern PR1 is notformed. The light conversion layer 120 f may be provided in the secondpixel area by coating or dropping the light conversion layer in fluidform and may be cured.

Referring to FIG. 14E, the first photoresist pattern PR1 is removed froman area except for the area in which the light conversion layer 120 f isformed. After the first photoresist pattern PR1 is removed, the uppersurface of the substrate 10, which corresponds to a first pixel area anda third pixel area, is exposed.

Referring to FIG. 14F, the light passing layer 120 is formed on theentire surface of the substrate 10 including the first and third pixelareas. In this case, the light passing layer 120 does not include aportion of the light passing layer, which serves as the light conversionlayer 120 f, and the light passing layer 120 may be formed to have athickness sufficient to cover the whole of the light conversion layer120 f.

Referring to FIG. 14G, an upper surface of the light passing layer 120,which is formed at the sufficient thickness and includes the lightconversion layer 120 f, may be polished, and a height of the firstinsulation layer 161 and the light passing layer 120 (including thelight conversion layer 120 f) is flattened. The upper surface of thelight passing layer 120 may be flattened by using a chemical or physicalpolishing.

Referring to FIG. 14H, the adhesive layer 180 is formed on the lightpassing layer 120 of the flattened substrate 10. The adhesive layer 180may be provided at an amount and a height, by which the light emittingdevice is attached well, and the adhesive layer 180 may be providedusing an organic polymer having fluidity and may be cured after thelight emitting device 150 is mounted thereon.

Referring to FIG. 14I, the light emitting device 150 is attached ontothe substrate 10 on which the adhesive layer 180 is provided. Each lightemitting device 150 may be transferred onto the substrate 10 after beingmanufactured on a separate substrate 10.

Referring to FIG. 14J, the second insulation layer 163 is formed on thesubstrate 10 on which the light emitting device 150 is attached. Thesecond insulation layer 163 may cover the light passing layer 120, thefirst insulation layer 161, and the first, second, and third lightemitting devices 150 a, 150 b, and 150 c and may be provided in variousways. The contact holes CH are defined through the second insulationlayer 163 to expose the electrodes of the first, second, and third lightemitting devices 150 a, 150 b, and 150 c, and the second insulationlayer 163 through which the contact holes CH are defined may be easilyformed using a photolithography process after being coated.

FIGS. 14K to 14M show a process for forming the terminal part 170 on thesecond insulation layer 163 using a lift-off method as a representativeexample.

First, as shown in FIG. 14K, a second photoresist pattern PR2 is formedon the second insulation layer 163. The second photoresist pattern PR2is formed by coating a photoresist and exposing/developing thephotoresist. In this case, an area from which the photoresist is removedcorresponds to an area in which the terminal part 170 is formed.

Then, as shown in FIG. 14L, a conductive layer ML is formed on theentire surface of the substrate 10 on which the second photoresistpattern PR2 is formed. The conductive layer ML may include the materialfor forming the terminal part 170 and may have the single- ormulti-layer structure of the metal and/or metal alloy.

After that, as shown in FIG. 14M, the second photoresist pattern PR2 isremoved with the metal layer formed thereon, and thus the terminal part170 is formed on the second insulation layer 163.

The light emitting apparatus according to the exemplary embodiment maybe easily formed using the above-described method. In particular, sincethe pixels and the terminal part may be sequentially formed on thesubstrate using the conventional processes, e.g., a coating process, asilk-screen process, and a photolithography process, processes forseparately manufacturing the pixel units and mounting the pixel units onthe separate substrate are not necessary.

In the conventional art, a light emitting apparatus is completed byseparately manufacturing a light emitting device chip, separatelymanufacturing a PCB substrate on which a terminal part and wirings areformed, and attaching the light emitting device chip to the PCBsubstrate using a conductive paste. In this case, the terminal part andthe wirings are formed on the PCB substrate through complex processes offorming thru-holes penetrating through top and bottom of the PCBsubstrate and forming additional electrode and connection wirings, whichare electrically connected to each other through the thru-holes. Inaddition, since areas are additionally required in the PCB substrate toform the thru-holes, it is difficult to miniaturize pixels. The areasfor the thru-holes may be reduced by decreasing a diameter of thethru-holes, however in this case, it is difficult to form the thru-holesdue to the decreased diameter of the thru-holes, and a difficulty and acost in fabricating sharply increase.

In contrast, the light emitting apparatus according to the exemplaryembodiment is manufactured by forming the contact holes through theinsulation layer without employing the separate printed circuit boardand connecting the terminal part through the contact holes. Thus, thepixel may be miniaturized, and the light emitting apparatus may besimply manufactured at a low cost.

In the above drawings, the light emitting apparatus is shown withrespect to one pixel unit, however plural pixel units may besubstantially simultaneously formed on a large-sized substrate, and thelarge-sized substrate may be divided into individual display units ofvarious sizes through a cutting process. The term “display unit” means aunit in which one or plural pixel units are mounted on one substrate.The divided individual display units are assembled and mounted on a basesubstrate on which wirings or driving circuits are mounted, for example,on the printed circuit board, and thus the light emitting apparatus ordisplaying apparatus of various sizes may be manufactured.

According to the exemplary embodiment, the manufacturing method of thedisplaying apparatus includes the transferring method of stably andefficiently transferring plural light emitting devices. FIGS. 15A to 15Dare conceptual views sequentially showing the method of simultaneouslytransferring the plural light emitting devices. In the followingdescriptions, the red, green, and blue lights are implemented, and acase that uses the light conversion layer while the blue light emittingdiode is used as the light emitting device instead of the red lightemitting diode to display the red light will be described as arepresentative example. Accordingly, the blue light emitting device, thegreen light emitting device, and the blue light emitting device arerespectively provided in the red pixel, the green pixel, and the bluepixel.

Referring to FIG. 15A, a plurality of blue light emitting devices 150Bis formed on a first temporary substrate 10 p, and a plurality of greenlight emitting devices 150G is formed on a separate first temporarysubstrate 10 p.

The green light emitting devices 150G and the blue light emittingdevices 150B, which are formed on the separate temporary substrate 10 p,are transferred onto a third temporary substrate 10 r using a conveyingapparatus 190. The third temporary substrate 10 r may have heatresistance, flexibility, and/or viscosity and may be provided in theform of sheet. The third temporary substrate 10 r is a temporarysubstrate on which the light emitting devices are temporarily alignedbefore the blue light emitting devices 150B or the green light emittingdevices 150G are transferred onto a final substrate.

The light emitting devices 150, which are to be finally mounted, arearranged on the third temporary substrate 10 r to correspond to thepixels.

An additional process, e.g., a process of forming the electrode part,may be performed on the light emitting devices 150 on the thirdtemporary substrate 10 r. A temporary adhesive layer 183 is provided onthe third temporary substrate 10 r, the light emitting devices 150 isattached on the temporary adhesive layer.

Referring to FIG. 15B, the substrate 10, on which the light emittingdevices 150 are finally formed, is prepared. The adhesive layer 180 isprovided in locations corresponding to the light emitting devices 150.Here, the adhesive layer 180 may include an organic or inorganic polymeror may be a solder. In the exemplary embodiment, the solder of theadhesive layer 180 may include a eutectic material.

The third temporary substrate 10 r on which the light emitting devices150 are formed is gripped by the conveying apparatus 190 and inverted toface the substrate 10 with the light emitting devices 150 interposedtherebetween.

Referring to FIG. 15C, the third temporary substrate 10 r is presseddownward, and thus the light emitting devices 150 are attached to theadhesive layer 180. In the case where the adhesive layer 180 includesthe eutectic material, the third temporary substrate 10 r may be pressedat a eutectic temperature or more and a eutectic bonding is possiblethrough reflow. Since the third temporary substrate 10 r may haveflexibility, the light emitting devices 150 are effectively presseddownward and attached to the adhesive layer 180, and the light emittingdevices may be prevented from being separated from their locations andfrom being attached in an inclined manner.

Referring to FIG. 15D, after the light emitting devices 150 arecompletely attached to the adhesive layer 180 on the substrate 10, forexample, after the light emitting devices 150 are completely attached bythe eutectic solder, the third temporary substrate 10 r is removed. As aresult, the light emitting devices 150 are massively transferred ontothe substrate 10 as shown in FIG. 15E.

According to the above-described embodiment, it is possible tomanufacture the display apparatus in which the defects, for example, thelight emitting devices are separated from their locations or the lightemitting devices are inclinedly attached, are prevented as much aspossible.

FIG. 16 is a view showing processes of forming a plurality of pixelunits 110 using a substrate 10 of sufficient size and cutting thesubstrate 10 into display units 101 of various sizes, and FIG. 17 is aview showing a process of assembling and mounting the cut display units101 of various sizes on a base substrate 10 such as a printed circuitboard.

Referring to FIG. 16, the pixel units 110 may be formed on the substrate10 according to the above-described embodiments, and the substrate 10may be cut along a cutting line CL into the display units 101 of varioussizes. The display unit 101 may have various sizes by the cuttingprocess to include only one pixel unit 110 or to include two, four, orsix pixel units 110.

Referring to FIG. 17, the display units 101 having various sizes may beassembled to each other in proper form, and thus the displayingapparatuses of various sizes may be manufactured. In this case, the term“displaying apparatus” used herein indicates an electronic apparatusthat displays arbitrary visual information, such as a text, a video, aphotograph, and a 2- or 3-dimensional image, and hereinafter, thedisplaying apparatus manufactured by the above-described method will bedescribed.

FIG. 18 is a plan view showing a displaying apparatus manufactured bythe above-described manufacturing method, and FIG. 19 is an enlargedplan view showing a portion P3 of FIG. 18.

Referring to FIGS. 18 and 19, the displaying apparatus according to theexemplary embodiment may have various shapes, such as a closed polygonalshape with straight sides like a rectangular shape, a circular or ovalshape with a curved side, and a semi-circular or semi-oval shape with astraight side and a curved side. In the exemplary embodiment, thedisplaying apparatus having rectangular shape is shown.

The displaying apparatus may include the display units 101 assembled toinclude the pixel units 110. In the exemplary embodiment, each pixelunit 110 may include a green pixel, a red pixel, and a blue pixel, andthe first, second, and third pixels 111 a, 111 b, and 111 c maycorrespond to the green pixel, the red pixel, and the blue pixel,respectively. However, the pixel included in each pixel unit should notbe limited thereto or thereby. For instance, each pixel unit may includea cyan pixel, a magenta pixel, and a yellow pixel.

The pixel units 110 and/or the pixels 111 a, 111 b, and 111 c arearranged in a matrix form. The expression that the pixel units 110and/or the pixels 111 a, 111 b, and 111 c are arranged in the matrixform does not indicate only that the pixel units 110 and/or the pixels111 a, 111 b, and 111 c are arranged exactly in line along rows orcolumns, and detailed locations of the pixel units 110 and/or the pixels111 a, 111 b, and 111 c may be changed while being arranged along therows or columns taken as a whole, such as a zigzag form.

FIG. 20 is a block diagram showing a displaying apparatus according toan exemplary embodiment.

Referring to FIG. 20, the displaying apparatus according to theexemplary embodiment includes a timing controller 350, a scan driver310, a data driver 330, a line part, and pixel units. In a case wherethe pixel units include a plurality of pixels, each pixel isindividually connected to the scan driver 310 and the data driver 330via the line part.

The timing controller 350 receives various control signals and imagedata, which are required to drive the displaying apparatus, from anexternal source (e.g., a system that transmits the image data). Thetiming controller 350 rearranges the received image data and applies therearranged image data to the data driver 330. In addition, the timingcontroller 350 generates scan control signals and data control signals,which are required to drive the scan driver 310 and the data driver 330,and applies the generated scan control signals and the data controlsignals to the scan driver 310 and the data driver 330, respectively.

The scan driver 310 receives the scan control signals from the timingcontroller 350 and generates scan signals in response to the scancontrol signals.

The data driver 330 receives the data control signals from the timingcontroller 350 and generates data signals in response to the datacontrol signals.

The line part includes a plurality of signal lines. In detail, the linepart includes first lines 103 that connect the scan driver 310 and thepixels and second lines 102 that connect the data driver 330 and thepixels. In the exemplary embodiment, the first lines 103 may be scanlines, and the second lines 102 may be data lines. Accordingly,hereinafter the first lines and the second lines will be described asthe scan lines and the data lines, respectively. In addition, the linepart may further include lines that connect the timing controller 350and the scan driver 310, the timing controller 350 and the data driver330, or other components to each other to transmit signals.

The scan lines 103 transmit the scan signals generated by the scandriver 310 to the pixels. The data signals generated by the data driver330 are applied to the data lines 102. The data signals applied to thedata lines 102 are input to pixels of a horizontal pixel unit lineselected by the scan signal.

The pixels 111 a, 111 b, and 111 c are connected to the scan lines 103and the data lines 102. The pixels 111 a, 111 b, and 111 c selectivelyemit the light in response to the data signals provided from the datalines 102 when the scan signals from the scan lines 103 are appliedthereto. As an example, each of the pixels 111 a, 111 b, and 111 c emitsthe light at a brightness corresponding to the data signal appliedthereto during each frame period. The pixels 111 a, 111 b, and 111 c, towhich the data signals corresponding to a black brightness are applied,do not emit the light during corresponding frame period.

In the exemplary embodiment, the pixels 111 a, 111 b, and 111 c may bedriven in passive matrix or active matrix manners. When the displayingapparatus is driven in the active matrix manner, the displayingapparatus may be driven by being further supplied with first and secondpower sources in addition to the scan signals and the data signals.

FIG. 21A is a circuit diagram showing one pixel among pixels for apassive matrix type displaying apparatus. In this case, the pixel may beone of the pixels, e.g., the red pixel, the green pixel, and the bluepixel, and the first pixel 111 a is shown in the present exemplaryembodiment.

Referring to FIG. 21A, the first pixel 111 a includes the light emittingdevice 150 connected between the scan line 103 and the data line 102.The light emitting device 150 may be a light emitting diode includingthe first electrode and the second electrode. The first and secondelectrodes are respectively connected to the common pad and the data padof the light emitting apparatus. The common pad and the data pad may berespectively connected to the scan line 103 and the data line 102, orvice versa.

When a voltage equal to or greater than a threshold voltage is appliedto between the first electrode and the second electrode, the lightemitting device 150 emits the light at a brightness corresponding to alevel of the voltage applied thereto. That is, the light emission of thefirst pixel 111 a may be controlled by controlling a voltage of the scansignal applied to the scan line 103 and/or a voltage of the data signalapplied to the data line 102.

In the exemplary embodiment, one light emitting device 150 connectedbetween the scan line 103 and the data line 102 is shown, but the numberof the light emitting devices 150 connected between the scan line 103and the data line 102 should not be limited to one. That is, plurallight emitting devices 150 may be connected between the scan line 103and the data line 102, and in this case, the light emitting devices 150may be connected to each other in parallel or series.

FIG. 21B is a circuit diagram showing a first pixel 111 a among pixelsfor an active matrix type displaying apparatus. When the displayingapparatus is the active matrix type displaying apparatus, the firstpixel 111 a may be driven by being further supplied with the first andsecond power sources ELVDD and ELVSS in addition to the scan signals andthe data signals.

Referring to FIG. 21B. the first pixel 111 a includes one or more lightemitting devices 150 and a transistor part TFT connected to the lightemitting device 150.

A first electrode of the light emitting device 150 is connected to thefirst pixel power source ELVDD via the transistor part TFT, and a secondelectrode of the light emitting device 150 is connected to the secondpixel power source ELVSS. The first pixel power source ELVDD and thesecond pixel power source ELVSS may have different electric potentialsfrom each other. As an example, the second pixel power source ELVSS mayhave the electric potential lower than the electric potential of thefirst pixel power source ELVDD by the threshold voltage of the lightemitting device 150 or more. Each of the light emitting devices 150emits the light at a brightness corresponding to a driving currentcontrolled by the transistor part TFT.

According to the exemplary embodiment, the transistor part TFT includesfirst and second transistors M1 and M2 and a storage capacitor Cst.However, a configuration of the transistor part TFT should not belimited to the embodiment shown in FIG. 17B.

The first transistor M1 (switching transistor) includes a sourceelectrode connected to the data line 102, a drain electrode connected toa first node N1, and a gate electrode connected to the scan line 103.The first transistor M1 is turned on upon receiving the scan signalhaving the voltage sufficient to turn on the first transistor M1 throughthe scan line 103 to electrically connect the data line 102 and thefirst node N1. In this case, the data signal of the corresponding frameis applied to the data line 102, and thus the data signal is applied tothe first node N1. The storage capacitor Cst is charged with the datasignal applied to the first node N1.

The second transistor M2 (driving transistor) includes a sourceelectrode connected to the first pixel power source ELVDD, a drainelectrode connected to the first electrode of the light emitting device,and a gate electrode connected to the first node N1. The secondtransistor M2 controls an amount of the driving current supplied to thelight emitting device 150 in response to the voltage of the first nodeN1.

One electrode of the storage capacitor Cst is connected to the firstpixel power source ELVDD, and the other electrode of the storagecapacitor Cst is connected to the first node N1. The storage capacitorCst is charged with the voltage corresponding to the data signal appliedto the first node N1 and maintains the charged voltage until a datasignal of a next frame is provided.

For the convenience of explanation, FIG. 21B shows the transistor partTFT including two transistors. However, the number of the transistorsincluded in the transistor part TFT should not be limited to two, andthe configuration of the transistor part TFT may be changed in variousways. For example, the transistor part TFT may include more transistorsand more capacitors. In addition, in the present exemplary embodiment,configurations of the first and second transistors, the storagecapacitor, and the lines are not shown in detail, however the first andsecond transistors, the storage capacitor, and the lines may be changedin various ways within the scope of implementing the circuit accordingto the exemplary embodiment.

According to the exemplary embodiment, the large-sized displayingapparatus may be implemented by the displaying apparatus according tothe above-described embodiments alone, however, when regarding thedisplaying apparatus according to the above-described embodiments as onedisplay module, it is possible to implement a displaying apparatus witha larger area than that of the conventional displaying apparatus byassembling a plurality of display modules to each other. FIG. 22 is aperspective view showing a large-sized multi-module displaying apparatus1000 according to an exemplary embodiment.

Referring to FIG. 22, the multi-module displaying apparatus 1000 mayinclude a plurality of display modules DM, and FIG. 18 shows 4 by 4(4×4) display modules DM that form one multi-module displayingapparatus. In the present exemplary embodiment, the display modules DMmay have the structure of at least one of the above-describedembodiments. For instance, each display module DM may include a displaypart 100 and a base substrate 200 and may include a plurality of thedisplay units 101 having different areas from each other as the displaymodule DM shown in a first row and a first column of FIG. 18.

In the present exemplary embodiment, each of the display modules DM orat least some display modules may be independently driven. As anotherway, at least some display modules DM may be dependently driven inconjunction with other display modules DM. In the case where the displaymodules DM are driven in conjunction with each other, one image may bedisplayed as shown in FIG. 18.

In the present exemplary embodiment, the display modules DM have thesame size as each other, however the present disclosure should not belimited thereto or thereby. That is, at least one display module DM mayhave a size different from that of the other display modules DM. Inaddition, at least one display module DM may have a different number ofpixels from that of the other display modules DM, and thus they may havedifferent resolutions from each other. Further, in a case where theresolution of all areas does not need to be the same, the multi-moduledisplaying apparatus may be manufactured by arranging the displaymodules DM having different resolutions from each other.

FIG. 23 is a schematic plan view illustrating a displaying apparatusaccording to another exemplary embodiment and FIGS. 24A and 24B are aschematic plan view and a cross-sectional view illustrating a lightemitting device of the displaying apparatus according to the otherexemplary embodiment, respectively.

Referring to FIG. 23, a displaying apparatus 2000 comprises a panelsubstrate 210 and a plurality of light emitting devices 800.

The panel substrate 210 may comprise a circuit for a passive matrixdrive or an active matrix drive. In one exemplary embodiment, the panelsubstrate 210 may comprise wires and resistors therein, and in anotherembodiment, the panel substrate 210 may comprise wires, transistors, andcapacitors. The panel substrate 210 may also have pads on its topsurface allowing electrical access to the disposed circuit. Although thepresent disclosure describes that the panel substrate 210 comprises thecircuit, the panel substrate 210 may be a transparent substrate capableof transmitting light.

The plurality of light emitting devices 800 are arranged on the panelsubstrate 210. Each light emitting device 800 may constitute onesubpixel SP. The light emitting device 800 has first and secondelectrode pads 112 and 114, and the first and second electrode pads 112and 114 may be electrically connected to the panel substrate 210.

In the present disclosure, the light emitting devices 800 may comprise ablue light emitting device 802, a green light emitting device 804, and ared light emitting device 806. The blue light emitting device 802 may bean inorganic light emitting diode emitting blue light and may comprisean AlGaInN-based well layer. The green light emitting device 804 may bean inorganic light emitting diode emitting green light, and may comprisean AlGaInP-based well layer or an AlInGaN-based well layer. The redlight emitting device 806 may be an inorganic light emitting diodeemitting red light, and may comprise an AlGaInP-based well layer.Furthermore, the light emitting devices 800 are not limited to the lightemitting devices 802, 804, and 806 emitting light of a single color, andone light emitting device 800 may have a plurality of well layers havinga stacked structure so as to emit light of various colors such as blue,green, and red.

In the present disclosure, the blue light emitting device 802, the greenlight emitting device 804, and the red light emitting device 806 aredisposed in different subpixels SPs, respectively and one or more lightemitting devices may be disposed in one subpixel SP. Three subpixels SPsin which the blue light emitting device 802, the green light emittingdevice 804 and the red light emitting device 806 are disposed,respectively, may form one pixel P.

A specific example of the light emitting device 800 will be describedwith reference to FIGS. 24A to 24B. FIG. 24A is a schematic plan viewillustrating a light emitting device 800 according to an exemplaryembodiment, and FIG. 24B is a sectional view taken along the line AA′ inFIG. 24A. For convenience of explanation, first and second electrodepads 112 and 114 are illustrated as being disposed over, but the lightemitting device 800 may be flip-bonded on the panel substrate 210 ofFIG. 23, and in this case the first and second electrode pads 112 and114 may be disposed under.

Referring to FIGS. 24A and 24B, the light emitting device 800 maycomprise a light emitting structure 29, an ohmic-layer 33, an insulationlayer 31, the first electrode pad 112, and the second electrode pad 114,and a connection tip 55 b may be disposed on the light emitting device800.

The light emitting structure 29 comprises a first conductivity typesemiconductor layer 23, an active layer 25, and a second conductivitytype semiconductor layer 27. The active layer 25 may be disposed on thefirst conductivity type semiconductor layer 23, and the secondconductivity type semiconductor layer 27 may be disposed on the activelayer 25.

The active layer 25 may have a multi-quantum well structure inparticular. A wavelength of light emitted by the light emitting device800 may be varied according to a composition of the active layer 25, andthus it may become a blue light emitting device 802, a green lightemitting device 804, or a red light emitting device 806.

In addition, the first conductivity type semiconductor layer 23 may bean n-type semiconductor layer, and the second conductivity typesemiconductor layer 27 may be a p-type semiconductor layer. In thepresent disclosure, a mesa M may be formed over the first conductivitytype semiconductor layer 23. The mesa M may be formed by etching theactive layer 25 and the second conductivity type semiconductor layer 27,and may comprise a portion of the first conductivity type semiconductorlayer 23.

The ohmic-layer 33 may be disposed on the second conductivity typesemiconductor layer 27. The ohmic-layer 33 is in ohmic contact with thesecond conductivity type semiconductor layer 27. The ohmic-layer 33 maycomprise a reflection layer, and the reflection layer reflects lightgenerated in the active layer 25 to prevent the light from beingabsorbed by the first and second electrode pads 112 and 114 or asubstrate and lost. In one example, the ohmic-layer 33 may comprise anohmic-contact layer and a reflection layer. However, the presentdisclosure is not limited thereto, but the ohmic-layer 33 may be formedof a transparent metal layer or a transparent conductive oxide layer.

The insulation layer 31 may cover the ohmic-layer 33 and the mesa M, andmay also cover a portion of an upper surface and sides of the firstconductivity type semiconductor layer 23. As it will be described later,the insulation layer 31 may cover sides of a via hole formed forallowing the first electrode pad 112 to be electrically connected to thefirst conductivity type semiconductor layer 23. The insulation layer 31may be formed of a single layer or multiple layers of a silicon oxidelayer or a silicon nitride layer. Furthermore, the insulation layer 31may be formed of a distributed Bragg reflector.

The first electrode pad 112 is electrically connected to the firstconductivity type semiconductor layer 23. As illustrated in FIG. 24B,the first electrode pad 112 is disposed over the insulation layer 31,and electrically connected to the second conductivity type semiconductorlayer 27 through the via hole passing through the second conductivitytype semiconductor layer 27 and the active layer 25. As illustrated, thefirst electrode pad 112 may be directly connected to the firstconductivity type semiconductor layer 23. The insulation layer 31 coversthe sides of the via hole and prevents the first electrode pad 112 frombeing short-circuited to the second conductivity type semiconductorlayer 27 or the active layer 25.

The second electrode pad 114 is electrically connected to the secondconductivity type semiconductor layer 27. The second electrode pad 114may be disposed over the insulation layer 31, and electrically connectedto the ohmic-layer 33 through an opening formed in the insulation layer31. In the present disclosure, the ohmic-layer 33 is formed of aconductive material, and electrically connects the second electrode pad114 to the second conductivity type semiconductor layer 27.

One or more connection tips 55 b may be disposed over the insulationlayer 31, and may be disposed between the first electrode pad 112 andthe second electrode pad 114. The connection tip 55 b may be formed in aprocess of transferring the light emitting device 800 to the panelsubstrate 210. An upper surface of the connection tip 55 b may not be aflat surface but a generally irregular inclined surface, and may have anuneven structure. In addition, a plurality of connection tips 55 bdisposed on one light emitting device 800 may have different lengths oneanother. In the present disclosure, the connection tip 55 b may comprisean organic material such as poly dimethylpolysiloxane (PDMS), epoxy,acryl, color polyimide, or others. However, the present disclosure isnot limited thereto, but the connection tip 55 b may comprise a materialother than an organic material.

In the present disclosure, the plurality of connection tips 55 b may bedisposed on the light emitting device 800, and the plurality ofconnection tips 55 b may be arranged asymmetrically to a particulardirection. For example, as shown in FIG. 24A, three connection tips 55 bmay be disposed on the light emitting device 800, and the threeconnection tips 55 b may be arranged asymmetrically to the line BB′. Oneconnection tip 55 b is disposed on a left side of the line BB′, and theother two connection tips 55 b are disposed on a right side of the lineBB′.

FIG. 24C is a schematic cross-sectional view illustrating a modifiedexample of the light emitting device.

Referring to FIG. 24C, a light emitting device 800′ according to thepresent exemplary embodiment is generally similar to the light emittingdevice 800 described above, but there is a difference that theohmic-layer 33 is omitted. In describing the present disclosure, thesame contents as those described in the other exemplary embodiment willbe omitted in order to avoid redundancy.

As shown, since the ohmic-layer 33 is omitted, a second electrode pad114 may be electrically connected directly to a second conductivity typesemiconductor layer 27. Since the light emitting device 800′ has arelatively small size, current can be evenly spread over a wide area ofthe light emitting device 800′ even if the ohmic-layer 33 is omitted.

In the meantime, although the connection tip 55 b in the above exemplaryembodiment is illustrated and described as formed on the same side asthe surface where the first and second electrode pads 112 and 114 aredisposed on, the connection tip 55 b may be formed on an opposite sideof the light emitting device 800 to the first and second electrode pads112 and 114. Formation of the connection tip 55 b under the lightemitting device 800 is related to a method of transferring the lightemitting devices 800, and can be understood through a later descriptionof a method of transferring the light emitting devices 800.

FIGS. 25A to 25K are schematic cross-sectional views illustrating amethod of manufacturing a displaying apparatus according to the firstexemplary embodiment.

Referring to FIG. 25A, a light emitting device 800 is formed on asubstrate 51. The substrate 51 may be a substrate for growing the lightemitting device 800. The substrate 51, for example, may be a sapphiresubstrate or a GaN substrate for growing an AlInGaN-based semiconductorlayer, or a GaAs substrate for growing an AlInGaP-based semiconductorlayers. For example, if the light emitting device 800 is a blue lightemitting device 800 or a green light emitting device 800, the sapphiresubstrate or the GaN substrate may be used, and if the light emittingdevice 800 is a red light emitting device 800, the GaAs substrate may beused.

Referring to FIG. 25B, a first mask layer 53 is formed on the substrate51 so as to cover a plurality of light emitting devices 800. The firstmask layer 53 may be formed to completely cover the plurality of lightemitting devices 800, and may formed over the light emitting devices 800to have a predetermined thickness.

Referring to FIG. 25C, a plurality of holes Hs are formed in the firstmask layer 53. Each of the plurality of holes Hs may be formed over theplurality of light emitting devices 800, and at least one hole H may beformed on each of the light emitting devices 800. In the presentdisclosure, three holes Hs are formed on each light emitting device 800,and the three holes Hs are arranged asymmetrically to at least onedirection where the light emitting devices 800 are arranged. Here, thethree holes Hs in the drawing are arranged asymmetrically to a directionwhich is perpendicular to the direction where the light emitting devices800 are arranged.

The first mask layer 53 may be formed of a photosensitive material, andthe plurality of holes Hs may be formed through a photolithographyprocess. The plurality of holes Hs may be formed through an exposure anddevelopment processes, but the present disclosure is not necessarilylimited thereto, but an etching process may be used. The plurality ofholes Hs may be formed in a triangular shape as shown in the drawing.However, the number of holes Hs is not necessarily limited to three.

Referring to FIG. 25D, a connection layer 55 is formed on the first masklayer 53. The connection layer 55 is formed on the first mask layer 53while filling the plurality of holes Hs formed in the first mask layer53. Since at least one hole H is formed over each light emitting device800, the connection layer 55 may be connected to the light emittingdevice 800 through at least one hole H formed over the light emittingdevice 800. A connection portion 55 a connected to the light emittingdevice 800 by filling the hole H is formed together while the connectionlayer 55 is formed.

The connection layer 55 may be formed of an organic material such aspoly dimethylpolysiloxane (PDMS), epoxy, acryl, color polyimide, or thelike, but it is not limited thereto. Here, the connection layer 55 mayhave a light transmittance of 90% or more, and a refractive index may be1.4 to 1.7.

Referring to FIG. 25E, a first temporary substrate 57 is coupled to anupper surface of the connection layer 55. The first temporary substrate57 may be a polymer substrate such as PET, PEN, PI sheet, or others, ormay be a substrate such as glass, PC, PMMA, or others. When the firsttemporary substrate 57 is coupled to the upper surface of the connectionlayer 55, bubbles generated in the connection layer 55 in a vacuum statemay be removed, and a hardening process of the connection layer 55 maybe performed at a temperature lower than a melting point of the firstmask layer 53. In this process, the first temporary substrate 57 may becoupled to the connection layer 55.

When the first temporary substrate 57 is coupled to the connection layer55, the substrate 51 is removed from the light emitting devices 800 asin FIG. 25F. The substrate 51 may be removed by a laser lift-off processor a wet etching process. For example, if the substrate 51 is a sapphiresubstrate, the substrate 51 may be removed by the laser lift-off processor a chemical lift-off process, and if the substrate 51 is a GaAssubstrate, the GaAs substrate may be removed by the wet etching process.

Referring to FIG. 25G, the first mask layer 53 is removed from the lightemitting as devices 800 with the substrate 51 removed. The first masklayer 53 may be removed by using, for example, acetone, a dedicatedstriper, etching, or others. As the first mask layer 53 is removed, eachof the light emitting devices 800 is connected to the connection layer55 through the at least one connection portion 55 a and maintained asshown in the drawing.

Referring to FIG. 25H, after the first mask layer 53 is removed from thelight emitting devices 800, a second temporary substrate 59 is coupledto lower surfaces of the light emitting devices 800. The secondtemporary substrate 59 may be a rubber or UV sheet, or may be a polymersubstrate such as PET, PEN, PI sheet, or others, or a substrate such asglass, PC, PMMA, or others.

When coupling the second temporary substrate 59 to the light emittingdevices 800 is completed, the light emitting devices 800 are removedfrom the connection layer 55 by using the second temporary substrate 59as shown in FIG. 25I. By applying an external force in an oppositedirection to the first temporary substrate 57, i.e., downward, to thesecond temporary substrate 59 coupled to the light emitting devices 800,the at least one connection portion 55 a connected to the light emittingdevices 800 is cut, and the light emitting devices 800 are separatedfrom the connection layer 55.

The external force applied to the second temporary substrate 59 as shownin the drawing, may be applied in a direction perpendicular to theconnection layer 55 at one side of the second temporary substrate 59.Accordingly, each of the light emitting devices 800 may be separatedfrom the connection layer 55 in such a manner that the at least oneconnection portion 55 a connected to each light emitting device 800 issequentially cut from one side of the second temporary substrate 59.

Referring to FIG. 25J, the light emitting devices 800 separated from theconnection layer 55 are disposed on the second temporary substrate 59with a predetermined interval. In the meantime, a connection tip 55 bmay be formed on each of the light emitting devices 800 as a residuewhile the connection portion 55 a is cut. Accordingly, the connectiontip 55 b is formed of the same material as the connection layer 55, andformed while the connection portion 55 a is cut by an external force, sothat thicknesses of the connection tips 55 b may be irregular anddifferent from one another.

Referring to FIGS. 25J and 25K, a portion of the light emitting devices800 disposed on the second temporary substrate 59 is transferred toanother substrate by using a pickup 70. The pickup 70 may comprise anelastomeric stamp, for example.

The pickup 70 picks up and transfers a portion of the plurality of lightemitting devices 800, and selectively picks up the light emittingdevices 800 arranged in accordance with an interval of the panelsubstrate 210. Accordingly, as shown in the drawing, the pickup 70doesn't pick up adjacent light emitting devices 800 together, but picksup the light emitting devices 800 at a certain interval at a time. Theinterval of the light emitting devices 800 to be picked up may varydepending on an interval of pixels in the panel substrate 210 onto whichthe light emitting devices 800 is transferred.

The pickup 70 picks up the light emitting devices 800 disposed with aninterval matching an interval of the pixels Ps shown in FIG. 23, and oneof the blue light emitting device 802, the green light emitting device804, and the red light emitting device 806 may be picked up to bearranged in one pixel P.

In the present disclosure, the light emitting devices 800 may be pickedup with the first and second electrode pads 112 and 114 disposedthereon. Accordingly, an additional temporary substrate may be used in aprocess of mounting the light emitting devices 800 on the panelsubstrate 210 by using the pickup 70. That is, the light emittingdevices 800 picked up through the pickup 70 may be first arranged on theadditional temporary substrate at the interval of the pixels Ps. Theblue light emitting device 802, the green light emitting device 804, andthe red light emitting device 806 may be all arranged on the additionaltemporary substrate at the interval of the pixels Ps. The blue lightemitting devices 802, the green light emitting devices 804, and the redlight emitting devices 806 disposed on the additional temporarysubstrate may be transferred to the panel substrate 210 at once. Thelight emitting devices 800 may be transferred for the first and secondelectrode pads 112 and 114 to be bonded to the panel substrate 210.

FIGS. 26A to 26L are schematic cross-sectional views illustrating amethod of manufacturing a displaying apparatus according to a secondexemplary embodiment.

Referring to FIG. 26A, light emitting devices 800 are formed on asubstrate 51. The substrate 51 may be a substrate for growingsemiconductor layers of the light emitting devices 800. If the lightemitting device 800 is a blue light emitting device 802 or a green lightemitting device 804, a sapphire substrate or a GaN substrate may beused, and if the light emitting device 800 is a red light emittingdevice 806, a GaAs substrate may be used.

Referring to FIG. 26B, a first mask layer 53 is formed on the substrate51 to cover a plurality of light emitting devices 800. The first masklayer 53 may be formed to cover all of the plurality of light emittingdevices 800, and may be formed over the light emitting devices 800 tohave a predetermined thickness.

Subsequently, referring to FIG. 26C, a plurality of holes Hs are formedin the first mask layer 53. At least one hole H may be formed on each ofthe light emitting devices 800. In the present disclosure, three holesHs are formed on each light emitting device 800, and the three holes Hsare arranged asymmetrically to at least one direction where the lightemitting devices 800 are arranged. Here, the three holes Hs in thedrawing are arranged asymmetrically to a direction which isperpendicular to the direction where the light emitting devices 800 arearranged.

The first mask layer 53 may be formed of a photosensitive material, andthe plurality of holes Hs may be formed through a photolithographyprocess. For example, the holes Hs may be formed through an exposure anddevelopment processes, but it is not limited thereto, but an etchingprocess may be used. The plurality of holes Hs may be formed in atriangular shape as shown in the drawing.

Referring to FIG. 26D, a connection layer 55 is formed on the first masklayer 53. The connection layer 55 is formed on the first mask layer 53while filling the plurality of holes Hs formed in the first mask layer53. Since each of the plurality of holes Hs is formed over the lightemitting device 800, the connection layer 55 may be connected to thelight emitting devices 800 through at least one hole H formed over thelight emitting device 800. A portion of the connection layer 55 may forma connection portion 55 a by filling the at least one hole H formed overthe light emitting device 800.

The connection layer 55 may be formed of an organic material such aspoly dimethylpolysiloxane (PDMS), epoxy, acryl, color polyimide, or thelike, but it is not limited thereto. Here, the coupling layer 55 mayhave a light transmittance of 90% or more, and a refractive index may be1.4 to 1.7.

Referring to FIG. 26E, a first temporary substrate 57 is coupled to anupper surface of the connection layer 55. The first temporary substrate57 may be a polymer substrate such as PET, PEN, PI sheet, or others, ormay be a substrate such as glass, PC, PMMA, or others. A film layer 61and a buffer layer 63 may be disposed between the first temporarysubstrate 57 and the connection layer 55, respectively. For example, thefilm layer 61 may be disposed over the connection layer 55, the bufferlayer 63 may be disposed over the film layer 61, and the first temporarysubstrate 57 may be disposed over the buffer layer 63. The buffer layer63 may be formed of a material melted by heat or UV irradiation.

When the first temporary substrate 57 is coupled to the upper surface ofthe connection layer 55, bubbles generated in the connection layer 55 ina vacuum state may be removed, and a hardening process of the connectionlayer 55 may be performed at a temperature lower than a melting point ofthe first mask layer 53. In this process, the first temporary substrate57 may be coupled to the connection layer 55.

Referring to FIG. 26F, the substrate 51 is removed from the lightemitting devices 800. The substrate 51 may be removed by a laserlift-off process or a wet etching process. For example, if a sapphiresubstrate, it may be removed by the laser lift-off process or a chemicallift-off process, and a GaAs substrate may be removed by the wet etchingprocess.

Referring to FIG. 4G, the first mask layer 53 is removed from the lightemitting devices 800 with the substrate 51 removed. The first mask layer53 may be removed by using, for example, acetone, a dedicated striper,dry etching, or others. Accordingly, the light emitting devices 800 areconnected to the connection layer 55 through at least one connectionportion 55 a connected to each light emitting device 800 and maintainedas shown in the drawing.

Referring to FIG. 26H, the first temporary substrate 57 coupled to anupper surface is removed. The first temporary substrate 57 may beremoved by irradiating heat or UV. The first temporary substrate 57 maybe removed without damaging the film layer 61 because the buffer layer63 is formed of a material melted by heat or UV irradiation.

Referring to FIG. 26I, a second temporary substrate 59 is coupled to alower surface of the light emitting devices 800. The second temporarysubstrate 59 may be a rubber or UV sheet, or may be a polymer substratesuch as PET, PEN, PI sheet, or others, or a substrate such as glass, PC,PMMA, or others.

When the second temporary substrate 59 is coupled to the light emittingdevices 800, the light emitting devices 800 are removed from theconnection layer 55 by using the second temporary substrate 59 as shownin FIG. 4J. By applying an external force downward to the secondtemporary substrate 59 coupled to the light emitting devices, the atleast one connection portion 55 a connected to the light emittingdevices 800 is cut, and the light emitting devices 800 are separatedfrom the connection layer 55.

The external force applied to the second temporary substrate 59 as shownin the drawing, may be applied in a direction perpendicular to theconnection layer 55 at one side of the second temporary substrate 59.Accordingly, each of the light emitting devices 800 may be separatedfrom the connection layer 55 in such a manner that the connectionportions 55 a connected to each light emitting device 800 issequentially cut.

Referring to FIG. 26K, the light emitting devices 800 separated from theconnection layer 55 are disposed on the second temporary substrate 59with a predetermined interval. At least one connection tip 55 b may beformed on each of the light emitting devices 800 as a residue while theconnection portion 55 a is cut. The connection tip 55 b is formed of thesame material as the connection layer 55, and formed while theconnection portion 55 a is cut by an external force, so that thicknessesof the connection tips 55 b may be different from one another. Also, thethicknesses of the connection tips 55 b may be less than thicknesses ofthe first and second electrode pads 112 and 114 as shown in the drawing.

And referring to FIGS. 26K and 26L, a portion of the light emittingdevices 800 disposed on the second temporary substrate 59 is transferredto another substrate by using a pickup 70. A substrate onto which thelight emitting devices 800 are transferred may be the panel substrate210 of the displaying apparatus 2000, or the light emitting devices 800may be transferred to a location for another process, if necessary.

FIGS. 27A to 27K are schematic cross-sectional views illustrating amethod of manufacturing a displaying apparatus according to a thirdexemplary embodiment.

Referring to FIG. 27A, a light emitting device 800 is formed on asubstrate 51. The substrate 51 is a substrate for growing semiconductorlayers of the light emitting device 800, and may be a sapphiresubstrate, a GaN substrate, or a GaAs substrate. For example, thesubstrate 51 may be the sapphire substrate if the light emitting device800 is a blue light emitting device 800 or a green light emitting device800, and it may be the GaAs substrate if the light emitting device 800is a red light emitting device 800.

Referring to FIG. 27B, a first mask layer 53 is formed on a substrate 51so as to cover a plurality of light emitting devices 800. The first masklayer 53 may be formed to completely cover the plurality of lightemitting devices 800, and may formed over the light emitting devices 800to have a predetermined thickness. The first mask layer 53 may be formedof a photosensitive material, for example.

Referring to FIG. 27C, a first temporary substrate 57 is coupled ontothe first mask layer 53. The first temporary substrate 57 may be apolymer substrate such as PET, PEN, PI sheet, or others, or may be asubstrate such as glass, PC, PMMA, or others. A buffer layer 63 may bedisposed between the first temporary substrate 57 and the first masklayer 53. The buffer layer 63 may be disposed on the first mask layer53, and the first temporary substrate 57 may be disposed on the bufferlayer 63.

Referring to FIG. 27D, the substrate 51 is removed from the lightemitting devices 800. The substrate 51 may be removed using a laserlift-off process, a wet etching process, or others. If the substrate 51is a sapphire substrate, the substrate 51 may be removed by the laserlift-off process or a chemical lift-off process. If the substrate 51 isa GaAs substrate, the substrate 51 may be removed by the wet etchingprocess.

Referring to FIG. 27E, a lower surface of the light emitting devices 800and a lower surface of the first mask layer 53 may be exposed as thesubstrate 51 is removed. A second mask layer 65 is formed under thelight emitting devices 800 and the first mask layer 53. The second masklayer 65 may cover the lower surface of the light emitting devices 800and may have a thickness smaller than that of the first mask layer 53.

Referring to FIG. 27F, a plurality of holes Hs are formed in the secondmask layer 65. At least one hole H may be formed under each lightemitting device 800. In the present disclosure, three holes Hs areformed under each light emitting device 800, and the three holes Hs arearranged asymmetrically to at least one direction where the lightemitting devices 800 are arranged. Here, the three holes Hs in thedrawing are arranged asymmetrically to a direction which isperpendicular to the direction where the light emitting devices 800 arearranged.

The second mask layer 65 may be formed with a photosensitive material asthe first mask layer 53, and the plurality of holes Hs may be formed bya photolithography process. The plurality of holes Hs may be formed in atriangular shape as shown in the drawing.

Referring to FIG. 27G, a connection layer 55 is formed under the secondmask layer 65. The connection layer 55 is formed under the second masklayer 65 while filling the plurality of holes Hs formed in the secondmask layer 65. Since each of the plurality of holes Hs is formed underthe light emitting device 800, the connection layer 55 may be connectedto the light emitting devices 800 through the holes Hs formed under thelight emitting devices 800. Connection portions 55 a filling the holesHs are formed together with the connection layer 55. The connectionportions 55 a may directly contact the first conductivity typesemiconductor layer 23.

The connection layer 55 may comprise an organic material such as polydimethylpolysiloxane (PDMS), epoxy, acryl, color polyimide, or the like,but it is not limited thereto. Here, the coupling layer 55 may have alight transmittance of 90% or more, and a refractive index may be 1.4 to1.7.

And a second temporary substrate 59 is coupled to a lower surface of theconnection layer 55. The second temporary substrate 59 may be a polymersubstrate the same as the first temporary substrate 57 such as PET, PEN,PI sheet, or others, or may be a substrate such as glass, PC, PMMA, orothers.

Referring to FIG. 27H, the first temporary substrate 57 coupled to anupper surface is removed. The first temporary substrate 57 may beremoved by irradiating heat or UV. The first temporary substrate 57 maybe removed from the first mask layer 53 because the buffer layer 63 isformed of a material melted by heat or UV irradiation.

Referring to FIG. 27I, the first mask layer 53 and the second mask layer65 are removed from the light emitting devices 800. The first mask layer53 and the second mask layer 65 may be removed by using, for example,acetone, a dedicated striper, dry etching, or others. As shown in thedrawing, the light emitting devices 800 are connected to the connectionlayer 55 by at least one connection portion 55 a connected to each lightemitting device 800 and maintained.

Once the first and second mask layers 53 and 65 are removed, the lightemitting devices 800 are disposed over the second temporary substrate 59while being connected to the connection layer 55 and the connectionportion 55 a as shown in FIG. 27J. A portion of the light emittingdevices 800 disposed over the second temporary substrate 59 may betransferred to another substrate using a pickup 70.

Referring to FIG. 27K, each of the light emitting devices 800 picked upby the pickup 70 is separated from the connection layer 55 by cuttingthe connection portion 55 a from the connection layer 55. The pickup 70picks up the light emitting devices 800 over the light emitting devices800, and the connection portion 55 a is disposed under the lightemitting device 800. Accordingly, at least one connection tip 55 b maybe formed under each of the light emitting devices 800.

FIGS. 28A to 28O are plan views illustrating modified examples of thelight emitting device.

In light emitting devices 800 according to the modified examples shownin FIGS. 28A to 28O as in another exemplary embodiment, a connection tip55 b is disposed on an opposite side to first and second electrode pads112 and 114. Hereinafter, for convenience of explanation, a location ofthe connection tip 55 b is described as a location relative to the firstand second electrode pads 112 and 114. However, the connection tip 55 band the first and second electrode pads 112 and 114 are disposed onopposite sides of the light emitting device 800, and they do not contacteach other.

Referring to FIG. 28A, in a first modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, anddisposed between the first and second electrode pads 112 and 114. Thatis, the three connection tips 55 b are formed on an upper surface of thelight emitting device 800. The first and second electrode pads 112 and114 are formed under the light emitting device 800. A shape of the threeconnection tips 55 b may be formed in a triangular shape. At this time,a total area of the three connection tips 55 b may be 1.26% as comparedwith a planar area of the light emitting device 800.

Referring to FIG. 28B, in a second modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, anddisposed outside of the first and second electrode pads 112 and 114. Twoconnection tips 55 b are disposed near the first electrode pad 112, anddisposed near two outer corners of the first electrode pad 112. And oneremaining connection tip 55 b is disposed outside the second electrodepad 114. At this time, the two connection tips 55 b disposed on sides ofthe first electrode pad 112 may be disposed in a direction differentfrom a direction where the first and second electrode pads 112 and 114are disposed.

And a total area of the three connection tips 55 b may be 0.65% ascompared with the planar area of the light emitting device 800.

Referring to FIG. 28C, in a third modified example, four connection tips55 b formed on the light emitting device 800 are provided, and arewidely disposed on the plane of the light emitting device 800. That is,two of the four connection tips 55 b are disposed at a locationoverlapping with the first and second electrode pads 112 and 114, andthe other two are disposed between the first and second electrode pads112 and 114. At this time, each of the two connection tips 55 b disposedat a location overlapping with the first and second electrode pads 112and 114 may be disposed at centers of the first and second electrodepads 112 and 114.

Here, the connection tips 55 b may be formed in a diamond shape, and thefour connection tips 55 b may be disposed at each corner of the diamondshape. At this time, a total area of the four connection tips 55 b maybe 1.22% as compared with the planar area of the light emitting device800.

Referring to FIG. 28D, in a fourth modified example, four connectiontips 55 b formed in the light emitting device 800 are provided. Portionsof two of the four connection tips 55 b are disposed to overlap with thefirst and second electrode pads 112 and 114, and the other two aredisposed between the first and second electrode pads 112 and 114. Theconnection tips 55 b of the fourth modified example may be disposed at arelatively small interval as compared with the connection tips 55 b ofthe third modified example.

Each of the connection tips 55 b may be formed in a diamond shape, andthe four connection tips 55 b may be disposed at each corner of thediamond shape. At this time, a total area of the four connection tips 55b may be 1.22% as compared with the planar area of the light emittingdevice 800.

Referring to FIG. 28E, in a fifth modified example, four connection tips55 b formed in the light emitting device 800 are provided. Theconnection tips 55 b of the fifth modified example may be disposed inthe same manner as the connection tips 55 b of the third modifiedexample. At this time, a total area of the connection tips 55 b of thefifth modified example is formed larger than that of the connection tips55 b of the third modified example, and may be 2.71% as compared withthe planar area of the light emitting device 800.

Referring to FIG. 28F, in a sixth modified example, four connection tips55 b formed in the light emitting device 800 are provided. Theconnection tips 55 b of the sixth modified example may be disposed inthe same manner as the connection tips 55 b of the fourth modifiedexample. At this time, a total area of the connection tips 55 b of thesixth modified example is formed larger than that of the connection tips55 b of the fourth modified example, and may be 2.71% as compared withthe planar area of the light emitting device 800.

Referring to FIG. 28G, in a seventh modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, anddisposed at locations overlapping with the first and second electrodepads 112 and 114. That is, two connection tips 55 b are disposed atlocations overlapping with the first electrode pads 112, and theremaining connection tip 55 b is disposed at a location overlapping withthe second electrode pads 114. The two connection tips 55 b disposed ona side of the first electrode pad 112 may be disposed in a directiondifferent from a direction in which the first and second electrode padsare disposed.

A total area of the three connection tips 55 b may be 0.58% as comparedwith the planar area of the light emitting device 800.

Referring to FIG. 28H, in an eighth modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, anddisposed at locations overlapping with the first and second electrodepads 112. One of the three connection tips 55 b is disposed at alocation partially overlapping with the first electrode pad 112, and theother two connection tips 55 b are disposed at a location partiallyoverlapping with the second electrode pad 114. At this time, the threeconnection tips 55 b may be formed in a triangular shape, and the threeconnection tips 55 b may be disposed at each corner of the triangularshape. And the connection tips 55 b of the eighth modified example areformed larger than the connection tips 55 b of the first modifiedexample, and may be 2.76% as compared with the planar area of the lightemitting device 800.

Referring to FIG. 28I, in a ninth modified example, four connection tips55 b formed in the light emitting device 800 are provided, and disposedat locations overlapping with the first and second electrode pads 112and 114. Two of the four connection tips 55 b are disposed at locationsoverlapping with the first electrode pad 112, and the other two aredisposed at locations overlapping with the second electrode pad 114.Here, the connection tips 55 b of the ninth modified example may beformed in a triangular shape. And a total area of the connection tips 55b may be 1.68% as compared with the planar area of the light emittingdevice 800.

Referring to FIG. 28J, in a tenth modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, anddisposed at locations overlapping with the first and second electrodepads 112 and 114. One of the three connection tips 55 b is disposed at alocation overlapping with the first electrode pad 112, and the other twoare disposed at a location overlapping with the second electrode pad114. And a total area of the connection tips 55 b may be 1.26% ascompared with the planar area of the light emitting device 800.

Referring to FIG. 28K, in an eleventh modified example, three connectiontips 55 b formed in the light emitting device 800 are provided, and theconnection tips 55 b are disposed at locations overlapping with thefirst and second electrode pads 112 and 114. Two of the three connectiontips 55 b are disposed at locations overlapping with the first electrodepad 112, and the other one is disposed at a location overlapping withthe second electrode pad 114. And a total area of the connection tips 55b may be 1.26% as compared with the planar area of the light emittingdevice 800.

Referring to FIG. 28L, in a twelfth modified example, a connection tip55 b formed in the light emitting device 800 is disposed between thefirst and second electrode pads 112 and 114. The connection tip 55 b isformed to have a base 55 ba having a longitudinal length perpendicularto a direction where the first and second electrode pads 112 and 114 aredisposed, a first extension 55 bb disposed at one longitudinal end ofthe base 55 ba and extending toward the electrode pad 112, and a secondextension 55 bc disposed at the other longitudinal end of the base 55 baand extending toward the second electrode pad 114. At this time, each ofthe first and second extensions 55 bb and 55 bc may be formed in a shapehaving a narrower width as a distance from the base 55 ba increases.

At this time, a total area of the connection tip 55 b may be 1.92% ascompared with the planar area of the light emitting device 800.

Referring to FIG. 28M, in a thirteenth modified example, a connectiontip 55 b formed in the light emitting device 800 is disposed between thefirst and second electrode pads 112 and 114. The connection tip 55 b isformed to have a base 55 ba having a longitudinal length perpendicularto a direction where the first and second electrode pads are disposed, afirst extension 55 bb at a center of the base 55 ba extending toward theelectrode pad 112, and a second extension 55 bc at a center of the base55 ba extending toward the second electrode pad 114. At this time, eachof the first and second extensions 55 bb and 55 bc may be formed in ashape having a narrower width as a distance from the base 55 baincreases.

At this time, a total area of the connection tip 55 b may be 1.161% ascompared with the planar area of the light emitting device 800.

Referring to FIG. 28N, in a fourteenth modified example, four connectiontips 55 b formed in the light emitting device 800 are provided. Two ofthe four connection tips 55 b are disposed at locations overlapping withthe first and second electrode pads 112 and 114, and the other two aredisposed between the first and second electrode pads 112 and 114. Atthis time, each of the connection tips 55 b disposed on the first andsecond electrode pads 112 and 114 may be disposed at an edge of thefirst and second electrode pads 112 and 114, respectively. At this time,the connection tip 55 b overlapped with the first electrode pad 112 maybe disposed at a location close to the second electrode pad 114 from thefirst electrode pad 112, and the connection tip 55 b overlapped with thesecond electrode pad 114 may be disposed at a location close to thefirst electrode pad 112 from the second electrode pad 114. At this time,a total area of the four connection tips 55 b may be 0.49% as comparedwith the planar area of the light emitting device 800.

Referring to FIG. 28O, in the fifteenth modified example, fourconnection tips 55 b formed in the light emitting device 800 areprovided. One connection tip is disposed approximately at a center ofthe light emitting device 800, two connection tips are disposed atlocations overlapped with the second electrode pad 114, and oneconnection tips is disposed at a location overlapped with the firstelectrode pad 112. Three connection tips 55 b are disposed in atriangular shape at an outer periphery of the light emitting device 800,and the one connection tip 55 b at the center of the light emittingdevice 800 may be located in the triangle formed by the three connectiontips 55 b.

The two connection tips disposed at the locations overlapped with thesecond electrode pad 114 may be disposed near one edge of the secondelectrode pad 114, and may be disposed to be opposite to each other withrespect to an elongated straight line passing through the center.

In the meantime, the one connection tip disposed at the locationoverlapped with the first electrode pad 112 may be disposed near oneedge of the first electrode pad 112, and may be disposed apart from theelongated straight line passing through the center.

Each of the connection tips may have a right triangular shape, and theconnection tip disposed at the center of the light emitting device 800may be disposed in a direction opposite to the other connection tips asshown in the drawing.

When the light emitting devices are separated from the connection layerusing the connection tips, the connection tip overlapped with the firstelectrode pad 112 may be formed first, then the connection tip near thecenter may be formed, and the connection tips overlapped with the secondelectrode pad 114 may be formed last. Accordingly, the light emittingdevices may be easily separated from the connection layer, and it ispossible to prevent cracks that may occur in the light emitting device.

Furthermore, when the light emitting device 800 is picked up or mounted,the light emitting device 800 may be unstably picked up or mounteddepending on locations of the connection tips, and thus cracks may becaused. On the contrary, by arranging the connection tips at both sideedges of the light emitting device 800 and near the center of the lightemitting device 800, respectively, the light emitting device 800 may bestably picked up or mounted, and it is possible to prevent cracks thatmay occur in the light emitting device.

A total area of the four connection tips 55 b may be 0.8% as comparedwith the planar area of the light emitting device 800.

When areas of the connection tips 55 b formed in the light emittingdevice 800 are formed to be different from one another, Table 1 shows acomparison between area ratios of the connection tips 55 b and successprobabilities of picking up the light emitting device 800.

TABLE 1 Area ratio (Based on the area of the Pickup success rate of thelight emitting device) light emitting device  1st Modified Example 1.26%Not less than 50%  2nd Modified Example 0.65% Good  3rd Modified Example1.22% Not less than 50%  4th Modified Example 1.22% Not less than 50% 5th Modified Example 2.71% Bad  6th Modified Example 2.71% Bad  7thModified Example 0.58% Good  8th Modified Example 2.76% NG  9th ModifiedExample 1.68% Less than 50% 10th Modified Example 1.26% Not less than50% 11th Modified Example 1.26% About 50% 12th Modified Example 1.92%Less than 50% 13th Modified Example 1.61% Less than 50% 14th ModifiedExample 0.49% Good 15th Modified Example 0.8% Good

Through the first to fifteenth modified examples, it is confirmed thatthe pick-up success rate of the light emitting devices 800 issatisfactory when the area ratio of the connection tips 55 b is about1.2% or less as compared with the planar area of the light emittingdevice 800.

FIG. 29A is a schematic plan view illustrating a light emitting device811 according to another exemplary embodiment, and FIG. 29B is aschematic cross-sectional view taken along the line C-C′ in FIG. 29A.Although the first light emitting device 811 of one of the lightemitting devices used for the pixel P is exemplarily described, but itcan also be applied to other light emitting devices described later, forexample, a second and third light emitting devices 813 and 815.

Referring to FIGS. 29A and 29B, the first light emitting device 811 maycomprise a first conductivity type semiconductor layer 2110, an activelayer 2112, and a second conductivity type semiconductor layer 2114, anohmic-contact layer 2116, an insulation layer 2120, a first terminal2122, and a second terminal 2124. In the meantime, connection tips 55 bmay be disposed on a side of the first conductivity type semiconductorlayer 2110 opposite to the first terminal 2122 and the second terminal2124.

The first conductivity type semiconductor layer 2110, the active layer2112, and the second conductivity type semiconductor layer 2114 may begrown on a substrate. The substrate may be a variety of substratescapable of growing semiconductors such as a gallium nitride substrate, aGaAs substrate, a Si substrate, a sapphire substrate, especially apatterned sapphire substrate, or others. The growth substrate may beseparated from the semiconductor layers using techniques such asmechanical polishing, laser lift off, chemical lift off, or others.However, the present disclosure is not limited thereto, and a portion ofthe substrate may remain to form at least a portion of the firstconductivity type semiconductor layer 2110.

In the case of a light emitting device emitting green light,semiconductor layers may comprise indium gallium nitride (InGaN),gallium nitride (GaN), gallium phosphide (GaP), aluminum gallium indiumphosphide (AlGaInP), or aluminum gallium phosphide (AlGaP). In oneexemplary embodiment, in the case of a light emitting device emittingred light, semiconductor layers may comprise aluminum gallium arsenide(AlGaAs), gallium arsenide phosphide (GaAsP), aluminum gallium indiumphosphide, or gallium phosphide (GaP). In one exemplary embodiment, inthe case of a light emitting device emitting blue light, a semiconductorlayer may comprise gallium nitride (GaN), indium gallium nitride(InGaN), or zinc selenide (ZnSe).

The semiconductor layers comprise specifically the first conductivitytype semiconductor layer 2110, the active layer 2112, and the secondconductivity type semiconductor layer 2114. As the first conductivitytype and the second conductivity type are opposite in polarity, when thefirst conductivity type is n-type, the second conductivity type is p,and when the second conductivity type is p-type, the second conductivitytype is n-type

The first conductivity type semiconductor layer 2110, the active layer2112 and the second conductivity type semiconductor layer 2114 may beformed on a substrate in a chamber using a known method such as metalorganic chemical vapor deposition (MOCVD). In addition, the firstconductivity type semiconductor layer 2110 comprises n-type impurities(for example, Si, Ge, and Sn), and the second conductivity typesemiconductor layer 2114 comprises p-type impurities (for example, Mg,Sr and Ba). In one exemplary embodiment, the first conductivity typesemiconductor layer 2110 may comprise GaN or AlGaN containing Si as adopant, and the second conductivity type semiconductor layer 2114 maycomprise GaN or AlGaN containing Mg as a dopant.

Although each of the first conductivity type semiconductor layer 2110and the second conductivity type semiconductor layer 2114 is illustratedas a single layer in the drawings, these layers may be multiple layers,or may comprise superlattice layers. The active layer 2112 may comprisea single quantum well structure or a multiple quantum well structure,and a composition ratio of a nitride-based semiconductor is adjusted toemit a desired wavelength. For example, the active layer 2112 may emitblue light, green light, red light, or ultraviolet light.

The second conductivity type semiconductor layer 2114 and the activelayer 2112 have a mesa (M) structure and are disposed on the firstconductivity type semiconductor layer 2110. The mesa M may comprise thesecond conductivity type semiconductor layer 2114 and the active layer2112, and may comprise a portion of the first conductivity typesemiconductor layer 2110 as shown in FIG. 29B. When the mesa M isdisposed on a portion of the first conductivity type semiconductor layer2110, an upper surface of the first conductivity type semiconductorlayer 2110 may be exposed around the mesa M.

In addition, the mesa M may have a through hole 2114 a exposing thefirst conductivity type semiconductor layer 2110. The through hole 2114a may be disposed close to one side edge of the mesa M, but the presentdisclosure is not limited thereto, the through hole 2114 a may bedisposed at a center of the mesa M.

The ohmic-contact layer 2116 is disposed on the second conductivity typesemiconductor layer 2114 to be in ohmic-contact with the secondconductivity type semiconductor layer 2114. The ohmic-contact layer 2116may be formed as a single layer or a multiple layer, or may be formed ofa transparent conductive oxide layer or a metal layer. Examples of thetransparent conductive oxide layers include ITO, ZnO or others, andexamples of the metal layers include metals such as Al, Ti, Cr, Ni, Au,or an alloy thereof.

The insulation layer 2120 covers the mesa M and the ohmic-contact layer2116. Further, the insulation layer 2120 may cover an upper surface andside surfaces of the first conductivity type semiconductor layer 2110exposed around the mesa M. In the meantime, the insulation layer 2120may have an opening 2120 a exposing the ohmic-contact layer 2116 and anopening 2120 b exposing the first conductivity type semiconductor layer2110 in the through hole 2114 a. The insulation layer 2120 may be formedof a single- or multi-layer of a silicon oxide layer or a siliconnitride layer. In addition, the insulation layer 2120 may comprise aninsulated reflector, such as a distributed Bragg reflector.

The first terminal 2122 and the second terminal 2124 are disposed on theinsulation layer 2120. The first terminal 2122 may be electricallyconnected to the ohmic-contact layer 2116 through the opening 2120 a,and the second terminal 2124 may be electrically connected to the firstconductivity type semiconductor layer 2110 through the opening 2120 b.

The first and/or second terminals 2122 and 2124 may have a single-, or amulti-layer metal. The first and/or second terminals 2122 and 2124 mayinclude metals such as Al, Ti, Cr, Ni, Au, or an alloy thereof.

In the meantime, the connection tips 55 b may be disposed as describedwith reference to FIG. 28O, but the present disclosure is not limitedthereto, they may be disposed at other locations. However, it ispossible to effectively prevent occurrence of cracks in the lightemitting device by disposing the connection tips 55 b as described withreference to FIG. 28O.

In the exemplary embodiment, the light emitting device 811 is roughlydescribed with reference to drawings. The light emitting device 811 mayfurther include a layer with additional functionality in addition to theabove-mentioned layers. For instance, various layers, such as areflection layer that reflects the light, an additional insulation layerthat insulates specific components, and a solder prevention layer thatprevents a solder from being diffused, may be included in the lightemitting device 811.

In addition, when a flip-chip type light emitting device is formed, amesa may be formed in various shapes, locations and shapes of the firstand second terminals 2122 and 2124 may be variously changed. Inaddition, the ohmic-contact layer 2116 may be omitted, and the firstterminal 2122 may directly contact the second conductivity typesemiconductor layer 2114. Further, a second contact layer may be formedon the first conductivity type semiconductor layer 2110, and the secondterminal 2124 may be connected to the second contact layer as in thecase of the light emitting devices 511 and 611 described above.

FIG. 30A is a schematic plan view illustrating a pixel region Paaccording to another exemplary embodiment, and FIG. 30B is a schematiccross-sectional view taken along the line D-D′ in FIG. 30A. Here, thepixel Pa represents a region where a single pixel P is disposed in alight emitting module or a pixel unit including at least one pixel P.

Referring to FIGS. 30A and 30B, the pixel region Pa may comprise a basesubstrate 900, first to third light emitting devices 811, 813 and 815,alignment markers 901, a light blocking layer 902, an adhesive layer903, a step adjustment layer 905, connection layers 907 a, 907 b, and907 c, bumps 921, 923, 925 and 930, and a protection layer 909.

In the present exemplary embodiment, the base substrate 900 does notinclude a circuit. The base substrate 900 is a light-transmittingsubstrate such as a glass substrate, a quartz substrate, or a sapphiresubstrate.

Although a single pixel region Pa is shown here, a plurality of pixels Pmay be formed on the single base substrate 900.

The base substrate 900 is disposed on a light emitting surface of thedisplaying apparatus and light emitted from the light emitting devices811, 813, and 815 is emitted to outside through the base substrate 900.The base substrate 900 may have projections and depressions PR on thelight emitting surface, and light emission efficiency may be improvedthrough the projections and depressions PR, and more uniform light maybe emitted. The base substrate 900 may have a thickness of, for example,50 um to 500 um.

The light blocking layer 902 may comprise an absorbing material thatabsorbs light, such as carbon black. The light absorbing materialprevents the light generated in the light emitting devices 811, 813 and815 from leaking to a side in a region between the base substrate 900and the light emitting devices 811, 813 and 815, and thus contrast ofthe displaying apparatus may be improved.

The light blocking layer 902 may have a window for providing a lightpath so that the light generated in the light devices 811, 813, and 815is incident on the base substrate 900. For this purpose, the lightblocking layer 902 may be subjected to patterning to expose the basesubstrate 900. A width of the window may be smaller than that of thelight emitting device.

The adhesive layer 903 is attached on the base substrate 900. Theadhesive layer 903 may be attached to the entire surface of the basesubstrate 900, and used to attach the light emitting devices 811, 813,and 815. The adhesive layer 903 may fill the window formed in the lightblocking layer 902.

The adhesive layer 903 transmits light emitted from the light emittingdevices 811, 813, and 815 to a light-transmitting layer. The adhesivelayer 903 may comprise diffusers such as SiO2, TiO2, or ZnO to diffuselight. The light diffusing material prevents the light emitting devices811, 813, and 815 from being observed from the light emitting surface.

The alignment markers 901 (shown in FIG. 30A, but omitted in FIG. 30B)indicate locations for disposing the first to third light emittingdevices 811, 813, and 815. Alignment markers 901 may be formed on thebase substrate 900 or on the adhesive layer 903.

In the meantime, each of the first to third light emitting devices 811,813, and 815 are disposed on regions formed by the alignment markers901. The first to third light emitting devices 811, 813 and 815 may be agreen light emitting device, a red light emitting device, or a bluelight emitting device, for example. In the present exemplary embodiment,the first to third light emitting devices 811, 813 and 815 areillustrated as arranged in a triangle, but the present disclosure is notlimited thereto, they may be arranged linear.

The first to third light emitting devices 811, 813, and 815 may be thosedescribed above with reference to FIGS. 29A and 29B, but the presentdisclosure is not limited thereto, and various light emitting deviceshaving a horizontal or flip-chip structure may be used.

The step adjustment layer 905 covers the first to third light emittingdevices 811, 813, and 815. The step adjustment layer 905 has openings905 a exposing the first and second terminals 2122 and 2124 of the lightemitting devices. The step adjustment layer 905 may be formed toequalize a height of a location where the bumps are formed when formingthe bumps. The step adjustment layer 905 may be formed of polyimide, forexample.

Connection layers 907 a and 907 c are formed on the step adjustmentlayer 905. Connection layers 907 a, 907 b, and 907 c are electricallyconnected to the first and second terminals 2122 and 2122 of the firstto third light emitting devices 811, 813, and 815 through the openings905 a of the step adjustment layer 905.

For example, the connection layers 907 a are electrically connected tothe first conductivity type semiconductor layer of the second lightemitting device 813, and the connection layer 907 c is electricallyconnected to the second conductivity type semiconductor layers of thefirst to third light emitting devices 811, 813, and 185. The connectionlayers 907 a and 907 c may be formed together on the step adjustmentlayer 905, and may include Au, for example.

Bumps 921, 923, 925, and 930 are formed on the connection layers 907 a.For example, the first bump 921 may be electrically connected to thefirst conductivity type semiconductor layer of the first light emittingdevice 811 through the connection layer 907 a, and the second bump 923may be electrically connected to the first conductivity typesemiconductor layer of the second light emitting device 813 through theconnection layer 907 a, and the third bump 925 may be electricallyconnected to the first conductivity type semiconductor layer of thethird light emitting device 815 through the connection layer 907 a. Inthe meantime, the fourth bump 930 may be commonly connected to thesecond conductivity type semiconductor layers of the first to thirdlight emitting devices 811, 813, and 815 through the connection layer907 c. The bumps 921, 923, 925, and 930 may be formed of a solder forexample.

In the meantime, a protection layer 909 may cover side surfaces of thebumps 921, 923, 925, and 930, and may cover the step adjustment layer905. Further, the protection layer 909 may cover the adhesive layer 903exposed around the step adjustment layer 905. The protection layer 909may be formed of a photosensitive solder resist (PSR), for example, andthus the bumps 921, 923, 925, and 930 may be formed after patterning theprotection layer 909 through photolithography and development. Theprotection layer 909 may also be formed of a light-absorbing materialsuch as a white reflective material or black epoxy to prevent lightleakage.

Although certain exemplary embodiments and implementations have beendescribed herein, other embodiments and modifications will be apparentfrom this description. Accordingly, the inventive concepts are notlimited to such embodiments, but rather to the broader scope of theappended claims and various obvious modifications and equivalentarrangements as would be apparent to a person of ordinary skill in theart.

What is claimed is:
 1. A displaying apparatus, comprising: a panelsubstrate; and a pixel region disposed on the panel substrate, whereinthe pixel region comprises: a plurality of light emitting devices; bumpselectrically connected to the light emitting devices; a base substratedisposing opposite to the bumps and transmitting light emitted from thelight emitting devices; and an adhesive layer disposed between the basesubstrate and the light emitting devices to adhere the light emittingdevices to the base substrate; wherein each of the light emittingdevices comprises: a light emitting structure comprising a firstconductivity type semiconductor layer, a second conductivity typesemiconductor layer, and an active layer interposed between the firstand second conductivity type semiconductor layers; and first and secondelectrode pads disposed on the light emitting structure, and wherein thebumps are electrically connected to the first and second pads of thelight emitting devices.
 2. The displaying apparatus of claim 1, whereinthe pixel region further comprises: a step adjustment layer disposedbetween the bumps and the light emitting devices to cover the lightemitting devices; and wherein the step adjustment layer and the adhesivelayer cover side surfaces of the light emitting devices.
 3. Thedisplaying apparatus of claim 2, further comprising: a protection layercovering side surfaces of the bumps and the step adjustment layer. 4.The displaying apparatus of claim 2, wherein the pixel region furthercomprises at least one connection tip disposed on one surface of each ofthe light emitting devices.
 5. The displaying apparatus of claim 4,wherein the connection tips are buried in the adhesive layer.
 6. Thedisplaying apparatus of claim 2, further comprising: a light blockinglayer disposed between the adhesive layer and the base substrate,wherein the light blocking layer has a window transmitting lightgenerated in the light emitting device.
 7. The displaying apparatus ofclaim 6, wherein a width of the window is smaller than that of the lightemitting device.
 8. The displaying apparatus of claim 6, wherein thewindow exposes the base substrate, and the adhesive layer fills thewindow.
 9. The displaying apparatus of claim 6, wherein the lightblocking layer comprises an absorbing material that absorbs light. 10.The displaying apparatus of claim 2, wherein the adhesive layer is alight transmitting layer comprising diffusers.
 11. The displayingapparatus of claim 2, wherein the pixel region further comprisesconnection layers formed on the step adjustment layer and electricallyconnecting the bumps to the first and second pads of the light emittingdevices.
 12. The displaying apparatus of claim 11, wherein the bumps areelectrically connected to the first conductivity type semiconductorlayers of the first to third light emitting device through theconnection layers, respectively, and the bump is commonly connected tothe second conductivity type semiconductor layers of the first to thirdlight emitting devices through the connection layer.
 13. The displayingapparatus of claim 11, wherein the bumps are electrically connected tothe second conductivity type semiconductor layers of the first to thirdlight emitting device through the connection layers, respectively, andthe bump is commonly connected to the first conductivity typesemiconductor layers of the first to third light emitting devicesthrough the connection layer.
 14. The displaying apparatus of claim 2,wherein the pixel region further comprises alignment markers disposed onthe base substrate or on the adhesive layer for indicating locations fordisposing the first to third light emitting devices.
 15. The displayingapparatus of claim 1, wherein the base substrate is a glass substrate, aquartz substrate, or a sapphire substrate.
 16. The displaying apparatusof claim 1, wherein the base substrate has projections and depressionson a surface thereof.
 17. The displaying apparatus of claim 1, whereinthe light emitting devices comprise a red light emitting device, a greenlight emitting device, and a blue light emitting device.
 18. Thedisplaying apparatus of claim 17, wherein the light emitting deviceshave a lateral or flip-chip structure.
 19. The displaying apparatus ofclaim 18, wherein the light emitting devices are arranged linear. 20.The displaying apparatus of claim 17, wherein the first conductivitytype semiconductor layers of the light emitting devices have a pluralityof concavo-convex portions provided on an opposite surface of a surfaceon which the active layer is disposed.